diff --git a/src/main/java/com/alibou/security/auth/AuthenticationService.java b/src/main/java/com/alibou/security/auth/AuthenticationService.java
index 53193a7..63c224a 100644
--- a/src/main/java/com/alibou/security/auth/AuthenticationService.java
+++ b/src/main/java/com/alibou/security/auth/AuthenticationService.java
@@ -21,6 +21,7 @@
 import org.springframework.stereotype.Service;
 
 import java.io.IOException;
+import java.util.Optional;
 
 @Service
 @RequiredArgsConstructor
@@ -32,17 +33,26 @@ public class AuthenticationService {
   private final AuthenticationManager authenticationManager;
 
   public AuthenticationResponse register(RegisterRequest request) {
-    var user = User.builder()
-        .firstname(request.getFirstname())
-        .lastname(request.getLastname())
-        .email(request.getEmail())
-        .password(passwordEncoder.encode(request.getPassword()))
-        .role(request.getRole())
-        .build();
-    var savedUser = repository.save(user);
+    // Check if the given user exists in database
+    Optional<User> userOptional = repository.findByEmail(request.getEmail());
+    User user;
+
+    if(userOptional.isPresent()) {
+      user = userOptional.get();
+    } else {
+      user = User.builder()
+              .firstname(request.getFirstname())
+              .lastname(request.getLastname())
+              .email(request.getEmail())
+              .password(passwordEncoder.encode(request.getPassword()))
+              .role(request.getRole())
+              .build();
+      repository.save(user);
+    }
+
     var jwtToken = jwtService.generateToken(user);
     var refreshToken = jwtService.generateRefreshToken(user);
-    saveUserToken(savedUser, jwtToken);
+    saveUserToken(user, jwtToken);
     return AuthenticationResponse.builder()
         .accessToken(jwtToken)
             .refreshToken(refreshToken)