diff --git a/backend/src/main/java/de/szut/casino/CasinoApplication.java b/backend/src/main/java/de/szut/casino/CasinoApplication.java
index 9a5db34..9e1f3b2 100644
--- a/backend/src/main/java/de/szut/casino/CasinoApplication.java
+++ b/backend/src/main/java/de/szut/casino/CasinoApplication.java
@@ -8,9 +8,6 @@ import org.springframework.boot.CommandLineRunner;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.annotation.Bean;
-import org.springframework.mail.MailException;
-import org.springframework.mail.MailSender;
-import org.springframework.mail.SimpleMailMessage;
 import org.springframework.mail.javamail.JavaMailSenderImpl;
 import org.springframework.web.client.RestTemplate;
 
diff --git a/backend/src/main/java/de/szut/casino/blackjack/BlackJackService.java b/backend/src/main/java/de/szut/casino/blackjack/BlackJackService.java
index 9bf591f..c417309 100644
--- a/backend/src/main/java/de/szut/casino/blackjack/BlackJackService.java
+++ b/backend/src/main/java/de/szut/casino/blackjack/BlackJackService.java
@@ -112,7 +112,6 @@ public class BlackJackService {
         dealCardToPlayer(game);
         dealCardToSplitHand(game);
 
-        return blackJackGameRepository.save(game);
     }
 
     private BlackJackGameEntity processGameBasedOnState(BlackJackGameEntity game) {
diff --git a/backend/src/main/java/de/szut/casino/config/OpenAPIConfiguration.java b/backend/src/main/java/de/szut/casino/config/OpenAPIConfiguration.java
index 7af90b9..75cac52 100644
--- a/backend/src/main/java/de/szut/casino/config/OpenAPIConfiguration.java
+++ b/backend/src/main/java/de/szut/casino/config/OpenAPIConfiguration.java
@@ -1,7 +1,6 @@
 package de.szut.casino.config;
 
 
-
 import io.swagger.v3.oas.models.Components;
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.info.Info;
diff --git a/backend/src/main/java/de/szut/casino/config/WebConfig.java b/backend/src/main/java/de/szut/casino/config/WebConfig.java
index bb11293..ecc21be 100644
--- a/backend/src/main/java/de/szut/casino/config/WebConfig.java
+++ b/backend/src/main/java/de/szut/casino/config/WebConfig.java
@@ -18,12 +18,12 @@ public class WebConfig {
             @Override
             public void addCorsMappings(CorsRegistry registry) {
                 registry.addMapping("/**")
-                    .allowedOrigins(frontendHost)
-                    .allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
-                    .allowedHeaders("*")
-                    .exposedHeaders("*")
-                    .allowCredentials(true)
-                    .maxAge(3600);
+                        .allowedOrigins(frontendHost)
+                        .allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
+                        .allowedHeaders("*")
+                        .exposedHeaders("*")
+                        .allowCredentials(true)
+                        .maxAge(3600);
             }
         };
     }
diff --git a/backend/src/main/java/de/szut/casino/deposit/DepositController.java b/backend/src/main/java/de/szut/casino/deposit/DepositController.java
index 522e47d..e64e428 100644
--- a/backend/src/main/java/de/szut/casino/deposit/DepositController.java
+++ b/backend/src/main/java/de/szut/casino/deposit/DepositController.java
@@ -53,8 +53,8 @@ public class DepositController {
                                 .build())
                         .setQuantity(1L)
                         .build())
-                .setSuccessUrl(frontendHost+"/home?success=true")
-                .setCancelUrl(frontendHost+"/home?success=false")
+                .setSuccessUrl(frontendHost + "/home?success=true")
+                .setCancelUrl(frontendHost + "/home?success=false")
                 .setMode(SessionCreateParams.Mode.PAYMENT)
                 .build();
 
diff --git a/backend/src/main/java/de/szut/casino/exceptionHandling/exceptions/EmailNotVerifiedException.java b/backend/src/main/java/de/szut/casino/exceptionHandling/exceptions/EmailNotVerifiedException.java
index ea08367..af97d4e 100644
--- a/backend/src/main/java/de/szut/casino/exceptionHandling/exceptions/EmailNotVerifiedException.java
+++ b/backend/src/main/java/de/szut/casino/exceptionHandling/exceptions/EmailNotVerifiedException.java
@@ -1,7 +1,5 @@
 package de.szut.casino.exceptionHandling.exceptions;
 
-import de.szut.casino.security.service.EmailService;
-
 public class EmailNotVerifiedException extends Exception {
     public EmailNotVerifiedException() {
         super("Email not verified");
diff --git a/backend/src/main/java/de/szut/casino/security/AuthController.java b/backend/src/main/java/de/szut/casino/security/AuthController.java
index 27949c5..13a238e 100644
--- a/backend/src/main/java/de/szut/casino/security/AuthController.java
+++ b/backend/src/main/java/de/szut/casino/security/AuthController.java
@@ -1,9 +1,7 @@
 package de.szut.casino.security;
 
-import de.szut.casino.exceptionHandling.ErrorDetails;
 import de.szut.casino.exceptionHandling.exceptions.EmailNotVerifiedException;
 import de.szut.casino.security.dto.AuthResponseDto;
-import de.szut.casino.security.dto.GithubCallbackDto;
 import de.szut.casino.security.dto.LoginRequestDto;
 import de.szut.casino.security.dto.ResetPasswordDto;
 import de.szut.casino.security.service.AuthService;
@@ -24,7 +22,7 @@ public class AuthController {
 
     @Autowired
     private AuthService authService;
-    
+
     @Autowired
     private GitHubService githubService;
 
@@ -42,11 +40,11 @@ public class AuthController {
 
     @PostMapping("/verify")
     public ResponseEntity<Void> verifyEmail(@RequestParam("token") String token) throws MessagingException, IOException {
-         if (authService.verifyEmail(token)) {
-             return ResponseEntity.badRequest().build();
-         }
+        if (authService.verifyEmail(token)) {
+            return ResponseEntity.badRequest().build();
+        }
 
-         return ResponseEntity.ok().build();
+        return ResponseEntity.ok().build();
     }
 
     @PostMapping("/recover-password")
diff --git a/backend/src/main/java/de/szut/casino/security/CorsFilter.java b/backend/src/main/java/de/szut/casino/security/CorsFilter.java
index 032088f..446864e 100644
--- a/backend/src/main/java/de/szut/casino/security/CorsFilter.java
+++ b/backend/src/main/java/de/szut/casino/security/CorsFilter.java
@@ -19,10 +19,10 @@ public class CorsFilter implements Filter {
 
     @Override
     public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
-        
+
         HttpServletResponse response = (HttpServletResponse) res;
         HttpServletRequest request = (HttpServletRequest) req;
-        
+
         // Allow requests from the frontend
         response.setHeader("Access-Control-Allow-Origin", frontendHost);
         response.setHeader("Access-Control-Allow-Methods", "GET, POST, PUT, PATCH, DELETE, OPTIONS");
@@ -30,12 +30,12 @@ public class CorsFilter implements Filter {
         response.setHeader("Access-Control-Expose-Headers", "*");
         response.setHeader("Access-Control-Allow-Credentials", "true");
         response.setHeader("Access-Control-Max-Age", "3600");
-        
+
         if ("OPTIONS".equalsIgnoreCase(request.getMethod())) {
             response.setStatus(HttpServletResponse.SC_OK);
             return;
         }
-        
+
         chain.doFilter(req, res);
     }
 }
diff --git a/backend/src/main/java/de/szut/casino/security/CustomJwtAuthenticationConverter.java b/backend/src/main/java/de/szut/casino/security/CustomJwtAuthenticationConverter.java
index 9f5304e..1997ac7 100644
--- a/backend/src/main/java/de/szut/casino/security/CustomJwtAuthenticationConverter.java
+++ b/backend/src/main/java/de/szut/casino/security/CustomJwtAuthenticationConverter.java
@@ -7,7 +7,7 @@ import org.springframework.security.oauth2.server.resource.authentication.JwtAut
 import org.springframework.security.oauth2.server.resource.authentication.JwtGrantedAuthoritiesConverter;
 
 public class CustomJwtAuthenticationConverter implements Converter<Jwt, AbstractAuthenticationToken> {
-    
+
     @Override
     public AbstractAuthenticationToken convert(Jwt source) {
         JwtGrantedAuthoritiesConverter authoritiesConverter = new JwtGrantedAuthoritiesConverter();
diff --git a/backend/src/main/java/de/szut/casino/security/GitHubController.java b/backend/src/main/java/de/szut/casino/security/GitHubController.java
index 9c2f2bf..ea1f23e 100644
--- a/backend/src/main/java/de/szut/casino/security/GitHubController.java
+++ b/backend/src/main/java/de/szut/casino/security/GitHubController.java
@@ -2,26 +2,14 @@ package de.szut.casino.security;
 
 import de.szut.casino.security.dto.AuthResponseDto;
 import de.szut.casino.security.dto.GithubCallbackDto;
-import de.szut.casino.security.jwt.JwtUtils;
-import de.szut.casino.user.AuthProvider;
-import de.szut.casino.user.UserEntity;
-import de.szut.casino.user.UserRepository;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
-import org.springframework.http.HttpEntity;
-import org.springframework.http.HttpHeaders;
-import org.springframework.http.HttpMethod;
 import org.springframework.http.ResponseEntity;
-import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.web.bind.annotation.*;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.servlet.view.RedirectView;
 
-import java.math.BigDecimal;
-import java.util.*;
-
 @RestController
 @RequestMapping("/oauth2/github")
 public class GitHubController {
@@ -42,12 +30,12 @@ public class GitHubController {
     @GetMapping("/authorize")
     public RedirectView authorizeGithub() {
         logger.info("Redirecting to GitHub for authorization");
-        
-        String authUrl = authorizationUri + 
-                "?client_id=" + clientId + 
-                "&redirect_uri=" + redirectUri + 
+
+        String authUrl = authorizationUri +
+                "?client_id=" + clientId +
+                "&redirect_uri=" + redirectUri +
                 "&scope=user:email,read:user";
-        
+
         return new RedirectView(authUrl);
     }
 
diff --git a/backend/src/main/java/de/szut/casino/security/GitHubService.java b/backend/src/main/java/de/szut/casino/security/GitHubService.java
index d6572d8..9ef8274 100644
--- a/backend/src/main/java/de/szut/casino/security/GitHubService.java
+++ b/backend/src/main/java/de/szut/casino/security/GitHubService.java
@@ -16,7 +16,6 @@ import org.springframework.http.ResponseEntity;
 import org.springframework.security.authentication.AuthenticationManager;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
 import org.springframework.security.core.Authentication;
-import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.crypto.password.PasswordEncoder;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestTemplate;
@@ -50,19 +49,19 @@ public class GitHubService {
         try {
             // Exchange code for access token
             RestTemplate restTemplate = new RestTemplate();
-            
+
             // Create request body for token endpoint
             Map<String, String> requestBody = new HashMap<>();
             requestBody.put("client_id", clientId);
             requestBody.put("client_secret", clientSecret);
             requestBody.put("code", code);
-            
+
             // Set headers
             HttpHeaders headers = new HttpHeaders();
             headers.set("Accept", "application/json");
-            
+
             HttpEntity<Map<String, String>> requestEntity = new HttpEntity<>(requestBody, headers);
-            
+
             // Get access token
             ResponseEntity<Map> response = restTemplate.exchange(
                     "https://github.com/login/oauth/access_token",
@@ -70,10 +69,10 @@ public class GitHubService {
                     requestEntity,
                     Map.class
             );
-            
+
             Map<String, Object> responseBody = response.getBody();
             logger.info("GitHub token response: {}", responseBody);
-            
+
             // Check if there's an error in the response
             if (responseBody.containsKey("error")) {
                 String error = (String) responseBody.get("error");
@@ -81,49 +80,49 @@ public class GitHubService {
                 logger.error("GitHub OAuth error: {} - {}", error, errorDescription);
                 throw new RuntimeException("GitHub OAuth error: " + errorDescription);
             }
-            
+
             String accessToken = (String) responseBody.get("access_token");
             if (accessToken == null || accessToken.isEmpty()) {
                 logger.error("No access token received from GitHub");
                 throw new RuntimeException("Failed to receive access token from GitHub");
             }
-            
+
             logger.info("Received access token from GitHub");
-            
+
             // Get user info
             HttpHeaders userInfoHeaders = new HttpHeaders();
             userInfoHeaders.set("Authorization", "Bearer " + accessToken);
 
             HttpEntity<String> userInfoRequestEntity = new HttpEntity<>(null, userInfoHeaders);
-            
+
             logger.info("Making request to GitHub API with token: {}", accessToken.substring(0, 5) + "...");
-            
+
             ResponseEntity<Map> userResponse = restTemplate.exchange(
                     "https://api.github.com/user",
                     HttpMethod.GET,
                     userInfoRequestEntity,
                     Map.class
             );
-            
+
             Map<String, Object> userAttributes = userResponse.getBody();
             logger.info("Retrieved user info from GitHub: {}", userAttributes.get("login"));
-            
+
             // Get user emails
             HttpHeaders emailsHeaders = new HttpHeaders();
             emailsHeaders.set("Authorization", "Bearer " + accessToken);
 
             HttpEntity<String> emailsRequestEntity = new HttpEntity<>(null, emailsHeaders);
-            
+
             ResponseEntity<List> emailsResponse = restTemplate.exchange(
                     "https://api.github.com/user/emails",
                     HttpMethod.GET,
                     emailsRequestEntity,
                     List.class
             );
-            
+
             List<Map<String, Object>> emails = emailsResponse.getBody();
             String email = null;
-            
+
             // Find primary email
             for (Map<String, Object> emailInfo : emails) {
                 Boolean primary = (Boolean) emailInfo.get("primary");
@@ -132,22 +131,22 @@ public class GitHubService {
                     break;
                 }
             }
-            
+
             // If no primary email, just use the first one
             if (email == null && !emails.isEmpty()) {
                 email = (String) emails.get(0).get("email");
             }
-            
+
             logger.info("Using email: {}", email);
-            
+
             // Process user data
             String githubId = userAttributes.get("id").toString();
             String username = (String) userAttributes.get("login");
-            
+
             // Check if user exists by provider ID
             Optional<UserEntity> userOptional = userRepository.findByProviderId(githubId);
             UserEntity user;
-            
+
             if (userOptional.isPresent()) {
                 // Update existing user
                 user = userOptional.get();
@@ -155,7 +154,7 @@ public class GitHubService {
             } else {
                 // Check if email exists
                 userOptional = userRepository.findByEmail(email);
-                
+
                 if (userOptional.isPresent()) {
                     user = userOptional.get();
                     user.setProvider(AuthProvider.GITHUB);
@@ -169,7 +168,7 @@ public class GitHubService {
                     user.setProvider(AuthProvider.GITHUB);
                     user.setProviderId(githubId);
                     user.setEmailVerified(true);
-                    
+
                     user.setBalance(new BigDecimal("1000.00"));
                     logger.info("Creating new user for: {}", username);
                 }
@@ -177,7 +176,7 @@ public class GitHubService {
 
             String randomPassword = UUID.randomUUID().toString();
             user.setPassword(oauth2PasswordEncoder.encode(randomPassword));
-            
+
             userRepository.save(user);
 
             Authentication authentication = this.authenticationManager.authenticate(new UsernamePasswordAuthenticationToken(user.getEmail(), randomPassword));
@@ -187,7 +186,7 @@ public class GitHubService {
             logger.info("Generated JWT token");
 
             return new AuthResponseDto(token);
-            
+
         } catch (Exception e) {
             logger.error("Error processing GitHub code", e);
             throw new RuntimeException("Failed to process GitHub authentication", e);
diff --git a/backend/src/main/java/de/szut/casino/security/SecurityConfig.java b/backend/src/main/java/de/szut/casino/security/SecurityConfig.java
index 3efbec7..9b3c880 100644
--- a/backend/src/main/java/de/szut/casino/security/SecurityConfig.java
+++ b/backend/src/main/java/de/szut/casino/security/SecurityConfig.java
@@ -1,8 +1,6 @@
 package de.szut.casino.security;
 
 import de.szut.casino.security.jwt.JwtAuthenticationFilter;
-import de.szut.casino.security.oauth2.CustomOAuth2UserService;
-import de.szut.casino.security.oauth2.OAuth2AuthenticationSuccessHandler;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.context.annotation.Bean;
@@ -33,7 +31,7 @@ public class SecurityConfig {
 
     @Value("${app.frontend-host}")
     private String frontendHost;
-    
+
     @Value("${app.oauth2.authorizedRedirectUris}")
     private String authorizedRedirectUri;
 
@@ -42,15 +40,15 @@ public class SecurityConfig {
 
     @Autowired
     private JwtAuthenticationFilter jwtAuthenticationFilter;
-    
+
 
     @Bean
     public DaoAuthenticationProvider authenticationProvider() {
         DaoAuthenticationProvider authProvider = new DaoAuthenticationProvider();
-        
+
         authProvider.setUserDetailsService(userDetailsService);
         authProvider.setPasswordEncoder(passwordEncoder());
-        
+
         return authProvider;
     }
 
@@ -67,18 +65,18 @@ public class SecurityConfig {
     @Bean
     public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {
         http
-            .cors(cors -> cors.configurationSource(corsConfigurationSource()))
-            .csrf(csrf -> csrf.disable())
-            .sessionManagement(session -> session.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
-            .authorizeHttpRequests(auth -> {
-                auth.requestMatchers("/auth/**", "/webhook", "/swagger/**", "/swagger-ui/**", "/health", "/error", "/oauth2/**").permitAll()
-                    .requestMatchers(org.springframework.http.HttpMethod.OPTIONS, "/**").permitAll()
-                    .anyRequest().authenticated();
+                .cors(cors -> cors.configurationSource(corsConfigurationSource()))
+                .csrf(csrf -> csrf.disable())
+                .sessionManagement(session -> session.sessionCreationPolicy(SessionCreationPolicy.STATELESS))
+                .authorizeHttpRequests(auth -> {
+                    auth.requestMatchers("/auth/**", "/webhook", "/swagger/**", "/swagger-ui/**", "/health", "/error", "/oauth2/**").permitAll()
+                            .requestMatchers(org.springframework.http.HttpMethod.OPTIONS, "/**").permitAll()
+                            .anyRequest().authenticated();
                 })
-            // Disable Spring's built-in OAuth2 login since we're implementing a custom flow
-            // We're using our own GitHubController for OAuth2 login
-            .authenticationProvider(authenticationProvider())
-            .addFilterBefore(jwtAuthenticationFilter, UsernamePasswordAuthenticationFilter.class);
+                // Disable Spring's built-in OAuth2 login since we're implementing a custom flow
+                // We're using our own GitHubController for OAuth2 login
+                .authenticationProvider(authenticationProvider())
+                .addFilterBefore(jwtAuthenticationFilter, UsernamePasswordAuthenticationFilter.class);
 
         return http.build();
     }
diff --git a/backend/src/main/java/de/szut/casino/security/dto/AuthResponseDto.java b/backend/src/main/java/de/szut/casino/security/dto/AuthResponseDto.java
index 0dd03dd..4dfe79a 100644
--- a/backend/src/main/java/de/szut/casino/security/dto/AuthResponseDto.java
+++ b/backend/src/main/java/de/szut/casino/security/dto/AuthResponseDto.java
@@ -12,7 +12,7 @@ import lombok.Setter;
 public class AuthResponseDto {
     private String token;
     private String tokenType = "Bearer";
-    
+
     public AuthResponseDto(String token) {
         this.token = token;
     }
diff --git a/backend/src/main/java/de/szut/casino/security/dto/LoginRequestDto.java b/backend/src/main/java/de/szut/casino/security/dto/LoginRequestDto.java
index ace3508..767a6d3 100644
--- a/backend/src/main/java/de/szut/casino/security/dto/LoginRequestDto.java
+++ b/backend/src/main/java/de/szut/casino/security/dto/LoginRequestDto.java
@@ -13,7 +13,7 @@ import lombok.Setter;
 public class LoginRequestDto {
     @NotBlank(message = "Username or email is required")
     private String usernameOrEmail;
-    
+
     @NotBlank(message = "Password is required")
     private String password;
 }
diff --git a/backend/src/main/java/de/szut/casino/security/jwt/JwtAuthenticationFilter.java b/backend/src/main/java/de/szut/casino/security/jwt/JwtAuthenticationFilter.java
index 502ba0a..38da0b3 100644
--- a/backend/src/main/java/de/szut/casino/security/jwt/JwtAuthenticationFilter.java
+++ b/backend/src/main/java/de/szut/casino/security/jwt/JwtAuthenticationFilter.java
@@ -35,11 +35,11 @@ public class JwtAuthenticationFilter extends OncePerRequestFilter {
 
                 if (username != null && SecurityContextHolder.getContext().getAuthentication() == null) {
                     UserDetails userDetails = userDetailsService.loadUserByUsername(username);
-                    
+
                     if (jwtUtils.validateToken(jwt, userDetails)) {
                         UsernamePasswordAuthenticationToken authToken = new UsernamePasswordAuthenticationToken(
                                 userDetails, null, userDetails.getAuthorities());
-                        
+
                         authToken.setDetails(new WebAuthenticationDetailsSource().buildDetails(request));
                         SecurityContextHolder.getContext().setAuthentication(authToken);
                     }
diff --git a/backend/src/main/java/de/szut/casino/security/oauth2/CustomOAuth2UserService.java b/backend/src/main/java/de/szut/casino/security/oauth2/CustomOAuth2UserService.java
index 51f52d8..de2de14 100644
--- a/backend/src/main/java/de/szut/casino/security/oauth2/CustomOAuth2UserService.java
+++ b/backend/src/main/java/de/szut/casino/security/oauth2/CustomOAuth2UserService.java
@@ -24,7 +24,7 @@ public class CustomOAuth2UserService extends DefaultOAuth2UserService {
 
     @Autowired
     private UserRepository userRepository;
-    
+
     @Autowired
     private PasswordEncoder oauth2PasswordEncoder;
 
@@ -44,7 +44,7 @@ public class CustomOAuth2UserService extends DefaultOAuth2UserService {
     private OAuth2User processOAuth2User(OAuth2UserRequest oAuth2UserRequest, OAuth2User oAuth2User) {
         String registrationId = oAuth2UserRequest.getClientRegistration().getRegistrationId();
         OAuth2UserInfo oAuth2UserInfo = OAuth2UserInfoFactory.getOAuth2UserInfo(registrationId, oAuth2User.getAttributes());
-        
+
         // For GitHub, the email might not be directly available in attributes
         String email = oAuth2UserInfo.getEmail();
         if (StringUtils.isEmpty(email)) {
@@ -53,16 +53,16 @@ public class CustomOAuth2UserService extends DefaultOAuth2UserService {
 
         Optional<UserEntity> userOptional = userRepository.findByEmail(email);
         UserEntity user;
-        
-        if(userOptional.isPresent()) {
+
+        if (userOptional.isPresent()) {
             user = userOptional.get();
-            
-            if(!user.getProvider().equals(AuthProvider.valueOf(registrationId.toUpperCase()))) {
-                throw new OAuth2AuthenticationProcessingException("You're signed up with " + 
-                        user.getProvider() + ". Please use your " + user.getProvider() + 
+
+            if (!user.getProvider().equals(AuthProvider.valueOf(registrationId.toUpperCase()))) {
+                throw new OAuth2AuthenticationProcessingException("You're signed up with " +
+                        user.getProvider() + ". Please use your " + user.getProvider() +
                         " account to login.");
             }
-            
+
             user = updateExistingUser(user, oAuth2UserInfo);
         } else {
             user = registerNewUser(oAuth2UserRequest, oAuth2UserInfo, email);
@@ -73,12 +73,12 @@ public class CustomOAuth2UserService extends DefaultOAuth2UserService {
 
     private UserEntity registerNewUser(OAuth2UserRequest oAuth2UserRequest, OAuth2UserInfo oAuth2UserInfo, String email) {
         UserEntity user = new UserEntity();
-        
+
         String username = oAuth2UserInfo.getName();
         if (StringUtils.isEmpty(username)) {
             username = "github_" + oAuth2UserInfo.getId();
         }
-        
+
         // Check if username already exists and append a suffix if needed
         if (userRepository.findByUsername(username).isPresent()) {
             username = username + "_" + UUID.randomUUID().toString().substring(0, 8);
@@ -89,13 +89,13 @@ public class CustomOAuth2UserService extends DefaultOAuth2UserService {
         user.setUsername(username);
         user.setEmail(email);
         user.setEmailVerified(true);
-        
+
         // Generate a random password for OAuth users (they won't use it)
         String randomPassword = UUID.randomUUID().toString();
         user.setPassword(oauth2PasswordEncoder.encode(randomPassword));
-        
+
         user.setBalance(new BigDecimal("1000.00")); // Starting balance
-        
+
         return userRepository.save(user);
     }
 
diff --git a/backend/src/main/java/de/szut/casino/security/oauth2/GitHubOAuth2UserInfo.java b/backend/src/main/java/de/szut/casino/security/oauth2/GitHubOAuth2UserInfo.java
index 2646956..baf8995 100644
--- a/backend/src/main/java/de/szut/casino/security/oauth2/GitHubOAuth2UserInfo.java
+++ b/backend/src/main/java/de/szut/casino/security/oauth2/GitHubOAuth2UserInfo.java
@@ -3,7 +3,7 @@ package de.szut.casino.security.oauth2;
 import java.util.Map;
 
 public class GitHubOAuth2UserInfo extends OAuth2UserInfo {
-    
+
     public GitHubOAuth2UserInfo(Map<String, Object> attributes) {
         super(attributes);
     }
diff --git a/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2AuthenticationSuccessHandler.java b/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2AuthenticationSuccessHandler.java
index 00d0b3e..6e4f1d0 100644
--- a/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2AuthenticationSuccessHandler.java
+++ b/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2AuthenticationSuccessHandler.java
@@ -1,7 +1,6 @@
 package de.szut.casino.security.oauth2;
 
 import de.szut.casino.security.jwt.JwtUtils;
-import de.szut.casino.user.UserEntity;
 import de.szut.casino.user.UserRepository;
 import jakarta.servlet.ServletException;
 import jakarta.servlet.http.HttpServletRequest;
@@ -26,7 +25,7 @@ public class OAuth2AuthenticationSuccessHandler extends SimpleUrlAuthenticationS
 
     @Autowired
     private JwtUtils jwtUtils;
-    
+
     @Autowired
     private UserRepository userRepository;
 
@@ -34,7 +33,7 @@ public class OAuth2AuthenticationSuccessHandler extends SimpleUrlAuthenticationS
     public void onAuthenticationSuccess(HttpServletRequest request, HttpServletResponse response, Authentication authentication)
             throws IOException, ServletException {
         String targetUrl = determineTargetUrl(authentication);
-        
+
         logger.info("OAuth2 Authentication successful, redirecting to: {}", targetUrl);
 
         if (response.isCommitted()) {
@@ -48,12 +47,12 @@ public class OAuth2AuthenticationSuccessHandler extends SimpleUrlAuthenticationS
 
     private String determineTargetUrl(Authentication authentication) {
         String token = jwtUtils.generateToken(authentication);
-        
+
         if (authentication.getPrincipal() instanceof UserPrincipal) {
             UserPrincipal userPrincipal = (UserPrincipal) authentication.getPrincipal();
             logger.info("User authenticated: ID={}, Email={}", userPrincipal.getId(), userPrincipal.getEmail());
         }
-        
+
         return UriComponentsBuilder.fromUriString(redirectUri)
                 .queryParam("token", token)
                 .build().toUriString();
diff --git a/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2UserInfoFactory.java b/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2UserInfoFactory.java
index 0d3c068..6f9c155 100644
--- a/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2UserInfoFactory.java
+++ b/backend/src/main/java/de/szut/casino/security/oauth2/OAuth2UserInfoFactory.java
@@ -6,9 +6,9 @@ import de.szut.casino.user.AuthProvider;
 import java.util.Map;
 
 public class OAuth2UserInfoFactory {
-    
+
     public static OAuth2UserInfo getOAuth2UserInfo(String registrationId, Map<String, Object> attributes) {
-        if(registrationId.equalsIgnoreCase(AuthProvider.GITHUB.toString())) {
+        if (registrationId.equalsIgnoreCase(AuthProvider.GITHUB.toString())) {
             return new GitHubOAuth2UserInfo(attributes);
         } else {
             throw new OAuth2AuthenticationProcessingException("Sorry! Login with " + registrationId + " is not supported yet.");
diff --git a/backend/src/main/java/de/szut/casino/security/oauth2/UserPrincipal.java b/backend/src/main/java/de/szut/casino/security/oauth2/UserPrincipal.java
index 113b945..6c993a0 100644
--- a/backend/src/main/java/de/szut/casino/security/oauth2/UserPrincipal.java
+++ b/backend/src/main/java/de/szut/casino/security/oauth2/UserPrincipal.java
@@ -64,7 +64,7 @@ public class UserPrincipal implements OAuth2User, UserDetails {
         // We're using email as the username for authentication
         return email;
     }
-    
+
     public String getDisplayUsername() {
         return username;
     }
diff --git a/backend/src/main/java/de/szut/casino/security/service/UserDetailsServiceImpl.java b/backend/src/main/java/de/szut/casino/security/service/UserDetailsServiceImpl.java
index b473a35..8d4018b 100644
--- a/backend/src/main/java/de/szut/casino/security/service/UserDetailsServiceImpl.java
+++ b/backend/src/main/java/de/szut/casino/security/service/UserDetailsServiceImpl.java
@@ -20,17 +20,17 @@ public class UserDetailsServiceImpl implements UserDetailsService {
     @Override
     public UserDetails loadUserByUsername(String usernameOrEmail) throws UsernameNotFoundException {
         Optional<UserEntity> user = userRepository.findByUsername(usernameOrEmail);
-        
+
         if (user.isEmpty()) {
             user = userRepository.findByEmail(usernameOrEmail);
         }
-        
-        UserEntity userEntity = user.orElseThrow(() -> 
+
+        UserEntity userEntity = user.orElseThrow(() ->
                 new UsernameNotFoundException("User not found with username or email: " + usernameOrEmail));
-        
+
         return new org.springframework.security.core.userdetails.User(
-                userEntity.getUsername(), 
-                userEntity.getPassword(), 
+                userEntity.getUsername(),
+                userEntity.getPassword(),
                 new ArrayList<>());
     }
 }
diff --git a/backend/src/main/java/de/szut/casino/user/UserEntity.java b/backend/src/main/java/de/szut/casino/user/UserEntity.java
index fa53b9a..c263d9c 100644
--- a/backend/src/main/java/de/szut/casino/user/UserEntity.java
+++ b/backend/src/main/java/de/szut/casino/user/UserEntity.java
@@ -1,11 +1,6 @@
 package de.szut.casino.user;
 
-import jakarta.persistence.Column;
-import jakarta.persistence.Entity;
-import jakarta.persistence.EnumType;
-import jakarta.persistence.Enumerated;
-import jakarta.persistence.GeneratedValue;
-import jakarta.persistence.Id;
+import jakarta.persistence.*;
 import lombok.Getter;
 import lombok.NoArgsConstructor;
 import lombok.Setter;
@@ -20,15 +15,15 @@ public class UserEntity {
     @Id
     @GeneratedValue
     private Long id;
-    
+
     @Column(unique = true)
     private String email;
-    
+
     @Column(unique = true)
     private String username;
-    
+
     private String password;
-    
+
     @Column(precision = 19, scale = 2)
     private BigDecimal balance;
 
@@ -37,10 +32,10 @@ public class UserEntity {
     private String verificationToken;
 
     private String passwordResetToken;
-    
+
     @Enumerated(EnumType.STRING)
     private AuthProvider provider = AuthProvider.LOCAL;
-    
+
     private String providerId;
 
     public UserEntity(String email, String username, String password, BigDecimal balance, String verificationToken) {
@@ -51,7 +46,7 @@ public class UserEntity {
         this.verificationToken = verificationToken;
         this.provider = AuthProvider.LOCAL;
     }
-    
+
     public UserEntity(String email, String username, AuthProvider provider, String providerId, BigDecimal balance) {
         this.email = email;
         this.username = username;
diff --git a/backend/src/main/java/de/szut/casino/user/UserMappingService.java b/backend/src/main/java/de/szut/casino/user/UserMappingService.java
index e244646..c93c132 100644
--- a/backend/src/main/java/de/szut/casino/user/UserMappingService.java
+++ b/backend/src/main/java/de/szut/casino/user/UserMappingService.java
@@ -5,7 +5,7 @@ import org.springframework.stereotype.Service;
 
 @Service
 public class UserMappingService {
-    
+
     public GetUserDto mapToGetUserDto(UserEntity user) {
         return new GetUserDto(user.getId(), user.getEmail(), user.getUsername(), user.getBalance());
     }
diff --git a/backend/src/main/java/de/szut/casino/user/UserRepository.java b/backend/src/main/java/de/szut/casino/user/UserRepository.java
index 36673b1..db28f49 100644
--- a/backend/src/main/java/de/szut/casino/user/UserRepository.java
+++ b/backend/src/main/java/de/szut/casino/user/UserRepository.java
@@ -9,13 +9,13 @@ import java.util.Optional;
 @Service
 public interface UserRepository extends JpaRepository<UserEntity, Long> {
     Optional<UserEntity> findByUsername(String username);
-    
+
     Optional<UserEntity> findByEmail(String email);
-    
+
     Optional<UserEntity> findByProviderId(String providerId);
-    
+
     boolean existsByUsername(String username);
-    
+
     boolean existsByEmail(String email);
 
     @Query("SELECT u FROM UserEntity u WHERE u.verificationToken = ?1")
diff --git a/backend/src/main/java/de/szut/casino/user/UserService.java b/backend/src/main/java/de/szut/casino/user/UserService.java
index baa2eab..03ad02d 100644
--- a/backend/src/main/java/de/szut/casino/user/UserService.java
+++ b/backend/src/main/java/de/szut/casino/user/UserService.java
@@ -27,15 +27,15 @@ public class UserService {
         if (userRepository.existsByEmail(createUserDto.getEmail())) {
             throw new EntityExistsException("Email is already in use");
         }
-        
+
         UserEntity user = new UserEntity(
-            createUserDto.getEmail(),
-            createUserDto.getUsername(),
-            passwordEncoder.encode(createUserDto.getPassword()),
-            BigDecimal.valueOf(100),
-            RandomStringUtils.randomAlphanumeric(64)
+                createUserDto.getEmail(),
+                createUserDto.getUsername(),
+                passwordEncoder.encode(createUserDto.getPassword()),
+                BigDecimal.valueOf(100),
+                RandomStringUtils.randomAlphanumeric(64)
         );
-        
+
         return userRepository.save(user);
     }
 
@@ -50,7 +50,7 @@ public class UserService {
     }
 
     public void saveUser(UserEntity user) {
-            userRepository.save(user);
+        userRepository.save(user);
     }
 
     public boolean isVerified(String usernameOrEmail) {
diff --git a/backend/src/main/java/de/szut/casino/user/dto/CreateUserDto.java b/backend/src/main/java/de/szut/casino/user/dto/CreateUserDto.java
index f9969cc..1be6ae3 100644
--- a/backend/src/main/java/de/szut/casino/user/dto/CreateUserDto.java
+++ b/backend/src/main/java/de/szut/casino/user/dto/CreateUserDto.java
@@ -16,11 +16,11 @@ public class CreateUserDto {
     @NotBlank(message = "Email is required")
     @Email(message = "Email should be valid")
     private String email;
-    
+
     @NotBlank(message = "Username is required")
     @Size(min = 3, max = 20, message = "Username must be between 3 and 20 characters")
     private String username;
-    
+
     @NotBlank(message = "Password is required")
     @Size(min = 6, message = "Password must be at least 6 characters")
     private String password;
diff --git a/backend/src/main/java/de/szut/casino/user/transaction/TransactionController.java b/backend/src/main/java/de/szut/casino/user/transaction/TransactionController.java
index 10061fa..8aa74a6 100644
--- a/backend/src/main/java/de/szut/casino/user/transaction/TransactionController.java
+++ b/backend/src/main/java/de/szut/casino/user/transaction/TransactionController.java
@@ -19,7 +19,7 @@ public class TransactionController {
             @RequestHeader("Authorization") String authToken,
             @RequestParam(value = "limit", required = false) Integer limit,
             @RequestParam(value = "offset", required = false) Integer offset
-            ) {
+    ) {
         UserTransactionsDto transactionEntities = this.transactionService.getUserTransactionsDto(authToken, limit, offset);
 
         return ResponseEntity.ok(transactionEntities);