I have implemented Sign in with Apple on website one weeks ago, and it work perfectly. However, recently we start to receive invalid_grant with no error description while token validation, however the same client secret works on IOS app without issue.... in ios app site , we used bundle id for client_id. in web site , we used service id for client_id; I try to create a new privateKey for web site and add redirect_uri params to /auth/token, but still error.... I tested it like this, i got authorization code using Service ID i tried authorization code with Service ID using browser : successfully got the code and requested access_token immately 2 and then, i tried validate the authorization grant code to obtain tokens curl like this curl -X POST https://appleid.apple.com/auth/token \ -H "Content-Type: application/x-www-form-urlencoded" \ -d "client_id=my_service_id" \ -d "client_secret=my_client_secret" \ -d "code=sent_from_frontend" \ -d "grant_type=authorization_code" \ -d "redirect_uri=my_redirect_uri" then get fail and no error_description error_code is 400 invalid_grant is not invalid_client error, and client secret is not expired too My decoded token looks like the following : { "alg": "ES256", "typ": "JWT", "kid": "my_kid" } { "aud": "https://appleid.apple.com", "sub": "my_service_id", "iss": "team_id", "exp": 1744012650, "iat": 1728460650 }