Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/config/filter/JWTAuthenticationFilter.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/config/filter/JWTAuthenticationFilter.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/config/filter/JWTAuthenticationFilter.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -6,4 +6,5 @@
 import jakarta.servlet.http.HttpServletResponse;
 import lombok.NonNull;
+import mk.ukim.finki.it.reservengo.constants.JWTConstants;
 import mk.ukim.finki.it.reservengo.service.intf.JWTService;
 import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
@@ -32,14 +33,14 @@
                                     @NonNull HttpServletResponse response,
                                     @NonNull FilterChain filterChain) throws ServletException, IOException {
-        final String authHeader = request.getHeader("Authorization");
+        final String authHeader = request.getHeader(JWTConstants.HEADER);
         final String jwt;
         final String userEmail;
 
-        if (authHeader == null || !authHeader.startsWith("Bearer ")) {
+        if (authHeader == null || !authHeader.startsWith(JWTConstants.TOKEN_PREFIX)) {
             filterChain.doFilter(request, response);
             return;
         }
 
-        jwt = authHeader.substring(7);
+        jwt = authHeader.substring(JWTConstants.TOKEN_PREFIX.length());
         userEmail = jwtService.extractUsername(jwt);
 
Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/constants/JWTConstants.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/constants/JWTConstants.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/constants/JWTConstants.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -0,0 +1,8 @@
+package mk.ukim.finki.it.reservengo.constants;
+
+public class JWTConstants {
+    public static final String SECRET_KEY = "7bce06d6331e532e8c4c85e6eaae4217711768fe1aa582b4549c2722a8ef0497";
+    public static final Long EXPIRATION_TIME = 864000000L; // 1 day
+    public static final String HEADER = "Authorization";
+    public static final String TOKEN_PREFIX = "Bearer ";
+}
Index: serveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/dto/adminDTO/AdminDTO.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/dto/adminDTO/AdminDTO.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ 	(revision )
@@ -1,6 +1,0 @@
-package mk.ukim.finki.it.reservengo.dto.adminDTO;
-
-public record AdminDTO(
-        String name
-) {
-}
Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/service/impl/JWTServiceImpl.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/service/impl/JWTServiceImpl.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/service/impl/JWTServiceImpl.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -6,4 +6,5 @@
 import io.jsonwebtoken.io.Decoders;
 import io.jsonwebtoken.security.Keys;
+import mk.ukim.finki.it.reservengo.constants.JWTConstants;
 import mk.ukim.finki.it.reservengo.model.domain.User;
 import mk.ukim.finki.it.reservengo.service.intf.JWTService;
@@ -17,7 +18,4 @@
 @Service
 public class JWTServiceImpl implements JWTService {
-
-    private static final String SECRET_KEY = "7bce06d6331e532e8c4c85e6eaae4217711768fe1aa582b4549c2722a8ef0497";
-
     @Override
     public String extractUsername(String token) {
@@ -37,5 +35,5 @@
     @Override
     public Key getSignInKey() {
-        byte[] keyBytes = Decoders.BASE64.decode(SECRET_KEY);
+        byte[] keyBytes = Decoders.BASE64.decode(JWTConstants.SECRET_KEY);
         return Keys.hmacShaKeyFor(keyBytes);
     }
@@ -54,5 +52,5 @@
                 .claim("id", user.getId())
                 .setIssuedAt(new Date())
-                .setExpiration(new Date(System.currentTimeMillis() + 1000 * 60 * 60 * 24))
+                .setExpiration(new Date(System.currentTimeMillis() + JWTConstants.EXPIRATION_TIME))
                 .signWith(getSignInKey(), SignatureAlgorithm.HS256)
                 .compact();
Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/AuthController.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/AuthController.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/AuthController.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -6,7 +6,9 @@
 import mk.ukim.finki.it.reservengo.service.intf.AuthService;
 import org.springframework.http.HttpStatus;
-import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.bind.annotation.*;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
 
 @RestController
@@ -19,5 +21,5 @@
     }
 
-    @PostMapping(value = "/register/customer", produces = MediaType.APPLICATION_JSON_VALUE)
+    @PostMapping(value = "/register/customer")
     public ResponseEntity<JWTAuthenticationResponseDTO> registerCustomer(@RequestBody JWTAuthenticationRequestDTO jwtAuthenticationRequestDTO) {
         return new ResponseEntity<>(authenticationService.registerCustomer(jwtAuthenticationRequestDTO), HttpStatus.CREATED);
Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/GlobalExceptionHandler.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/GlobalExceptionHandler.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/GlobalExceptionHandler.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -6,5 +6,4 @@
 import org.springframework.security.authentication.BadCredentialsException;
 import org.springframework.security.core.AuthenticationException;
-import org.springframework.security.core.userdetails.UsernameNotFoundException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
@@ -15,15 +14,15 @@
     @ExceptionHandler(BadCredentialsException.class)
     public ResponseEntity<String> handleBadCredentials(BadCredentialsException ex) {
-        return ResponseEntity.status(HttpStatus.UNAUTHORIZED).body("Invalid email or password");
+        return ResponseEntity.status(HttpStatus.UNAUTHORIZED).body(ex.getMessage());
     }
 
     @ExceptionHandler(EmailNotFoundException.class)
     public ResponseEntity<String> handleUserNotFound(EmailNotFoundException ex) {
-        return ResponseEntity.status(HttpStatus.NOT_FOUND).body("User not found");
+        return ResponseEntity.status(HttpStatus.NOT_FOUND).body(ex.getMessage());
     }
 
     @ExceptionHandler(AuthenticationException.class)
     public ResponseEntity<String> handleUserNotFound(AuthenticationException ex) {
-        return ResponseEntity.status(HttpStatus.NOT_FOUND).body("Authentication failed");
+        return ResponseEntity.status(HttpStatus.NOT_FOUND).body(ex.getMessage());
     }
 }
Index: ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/UserController.java
===================================================================
--- ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/UserController.java	(revision e0ee7c845f049eee8fad0357de1c9398cd160c1a)
+++ ReserveNGo-backend/src/main/java/mk/ukim/finki/it/reservengo/web/UserController.java	(revision bf7846471b6f817f2b231d28b707597d01be0eed)
@@ -20,7 +20,7 @@
 
     @GetMapping("/info")
-    public ResponseEntity<?> getUserPersonalInfo(@AuthenticationPrincipal User u) {
-        User user = userService.findUser(u.getId());
-        return ResponseEntity.ok(user);
+    public ResponseEntity<?> getUserPersonalInfo(@AuthenticationPrincipal User user) {
+        User u = userService.findUser(user.getId());
+        return ResponseEntity.ok(u);
     }