The 'identityToken' received in 'AsAuthorizationAppleIdCredential' contains a claim 'aud' which should be equal to your 'client_id' in your Apple Developer account. As part of JWT validation (https://developer.apple.com/documentation/signinwithapplerestapi/verifying_a_user), we have to verify that the 'aud' field is the developer’s 'client_id'. Currently, I am unable to set up my 'client_id' in 'ASAuthorizationAppleIDProvider' and hence the 'aud' claim in the 'identityToken' received in 'AsAuthorizationAppleIdCredential' contains the BundleId and not the client_Id.