diff --git a/src/main/java/com/fredmaina/chatapp/Auth/services/AuthService.java b/src/main/java/com/fredmaina/chatapp/Auth/services/AuthService.java
index 3364ab0..db9caeb 100644
--- a/src/main/java/com/fredmaina/chatapp/Auth/services/AuthService.java
+++ b/src/main/java/com/fredmaina/chatapp/Auth/services/AuthService.java
@@ -49,12 +49,12 @@ public class AuthService {
     @CacheEvict(value = "usernameCheck", key = "#request.username.toLowerCase()")
     public AuthResponse signUp(SignUpRequest request) {
         AuthResponse authResponse = new AuthResponse();
-        if (request.getUsername() != null && userRepository.findByUsernameIgnoreCase(request.getUsername()).isPresent()) {
-            authResponse.setMessage("Username already exists (case-insensitive)");
+        if (request.getUsername() != null && userRepository.existsByUsernameIgnoreCase(request.getUsername())) {
+            authResponse.setMessage("Username already exists");
             authResponse.setSuccess(false);
             return authResponse;
         }
-        if (userRepository.findByEmail(request.getEmail()).isPresent()) {
+        if (userRepository.existsByEmail(request.getEmail())) {
             authResponse.setMessage("Email already exists");
             authResponse.setSuccess(false);
             return authResponse;
@@ -80,14 +80,8 @@ public AuthResponse signUp(SignUpRequest request) {
             authResponse.setUser(user);
             authResponse.setToken(token);
         } catch (DataIntegrityViolationException e) {
-            if (e.getMessage().contains("users_email_key")) {
-                authResponse.setMessage("Email already exists");
-            } else if (e.getMessage().contains("idx_user_username") || e.getMessage().contains("users_username_key")) {
-                authResponse.setMessage("Username already exists");
-            } else {
-                log.error("Data integrity violation during sign up: {}", e.getMessage());
-                authResponse.setMessage("Data integrity violation");
-            }
+            log.error("Data integrity violation during sign up: {}", e.getMessage());
+            authResponse.setMessage("Data integrity violation");
             authResponse.setSuccess(false);
         } catch (Exception e) {
             log.error("Unexpected error during sign up: {}", e.getMessage(), e);
@@ -240,7 +234,6 @@ public AuthResponse setUsername(String email, String username) {
                         .message("Username set successfully")
                         .build();
             } catch (DataIntegrityViolationException e) {
-
                 log.error("Data integrity violation while setting username for email {}: {}", email, e.getMessage());
                 return AuthResponse.builder()
                         .message("Username already taken or another data issue occurred.")
diff --git a/src/test/java/com/fredmaina/chatapp/Auth/Services/AuthServiceTest.java b/src/test/java/com/fredmaina/chatapp/Auth/Services/AuthServiceTest.java
index b77792a..bec2dd7 100644
--- a/src/test/java/com/fredmaina/chatapp/Auth/Services/AuthServiceTest.java
+++ b/src/test/java/com/fredmaina/chatapp/Auth/Services/AuthServiceTest.java
@@ -11,7 +11,6 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.*;
-import org.springframework.dao.DataIntegrityViolationException;
 import org.springframework.security.crypto.password.PasswordEncoder;
 
 import java.util.Optional;
@@ -68,14 +67,13 @@ void testSignUp_duplicateEmail() {
         request.setPassword("mypassword");
         request.setEmail("fred@example.com");
 
-        when(passwordEncoder.encode(anyString())).thenReturn("encodedPassword");
-        when(userRepository.save(any(User.class))).thenThrow(
-                new DataIntegrityViolationException("users_email_key"));
+        when(userRepository.existsByEmail("fred@example.com")).thenReturn(true);
 
         AuthResponse response = authService.signUp(request);
 
         assertFalse(response.isSuccess());
         assertEquals("Email already exists", response.getMessage());
+        verify(userRepository, never()).save(any(User.class));
     }
 
     @Test
@@ -85,14 +83,13 @@ void testSignUp_duplicateUsername() {
         request.setPassword("mypassword");
         request.setEmail("fred@example.com");
 
-        when(passwordEncoder.encode(anyString())).thenReturn("encodedPassword");
-        when(userRepository.save(any(User.class))).thenThrow(
-                new DataIntegrityViolationException("users_username_key"));
+        when(userRepository.existsByUsernameIgnoreCase("fredmaina123")).thenReturn(true);
 
         AuthResponse response = authService.signUp(request);
 
         assertFalse(response.isSuccess());
         assertEquals("Username already exists", response.getMessage());
+        verify(userRepository, never()).save(any(User.class));
     }
 
     @Test