diff --git a/src/auth/auth-token.dto.ts b/src/auth/auth-token.dto.ts
index 46af7d6be..bd3ef8970 100644
--- a/src/auth/auth-token.dto.ts
+++ b/src/auth/auth-token.dto.ts
@@ -15,8 +15,8 @@ export class AuthTokenDto {
   createdAt: Date;
   @IsDate()
   @IsOptional()
-  validUntil: Date;
+  validUntil: Date | null;
   @IsDate()
   @IsOptional()
-  lastUsed: Date;
+  lastUsed: Date | null;
 }
diff --git a/src/auth/auth.service.spec.ts b/src/auth/auth.service.spec.ts
index 4240afb4e..b79f7f0bf 100644
--- a/src/auth/auth.service.spec.ts
+++ b/src/auth/auth.service.spec.ts
@@ -251,7 +251,7 @@ describe('AuthService', () => {
         });
         jest.spyOn(authTokenRepo, 'save').mockImplementationOnce(
           async (authTokenSaved: AuthToken, _): Promise<AuthToken> => {
-            expect(authTokenSaved.lastUsed).toBeUndefined();
+            expect(authTokenSaved.lastUsed).toBeNull();
             return authTokenSaved;
           },
         );
@@ -275,7 +275,7 @@ describe('AuthService', () => {
         });
         jest.spyOn(authTokenRepo, 'save').mockImplementationOnce(
           async (authTokenSaved: AuthToken, _): Promise<AuthToken> => {
-            expect(authTokenSaved.lastUsed).toBeUndefined();
+            expect(authTokenSaved.lastUsed).toBeNull();
             return authTokenSaved;
           },
         );
diff --git a/src/auth/auth.service.ts b/src/auth/auth.service.ts
index d81a8d5c5..76758e680 100644
--- a/src/auth/auth.service.ts
+++ b/src/auth/auth.service.ts
@@ -181,8 +181,6 @@ export class AuthService {
 
   toAuthTokenDto(authToken: AuthToken): AuthTokenDto {
     const tokenDto: AuthTokenDto = {
-      lastUsed: null,
-      validUntil: null,
       label: authToken.label,
       keyId: authToken.keyId,
       createdAt: authToken.createdAt,