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Hi,I'm trying to implement Sign in with Apple where the authorization code is obtained from the ASAuthorizationAppleIDCredential native API, then sent to our server for verification via the REST API.func authorizationController(controller: ASAuthorizationController, didCompleteWithAuthorization authorization: ASAuthorization) { guard let credential = authorization.credential as? ASAuthorizationAppleIDCredential else { return } let authorizationCode = String(data: credential.authorizationCode!, encoding: .utf8) }This is entirely successful. It uses an App ID with the correct entitlement.I'm then attempting to exchange this on the server-side:curl "https://appleid.apple.com/auth/token" \ -d "client_id=***" \ -d "client_secret=***" \ -d "grant_type=authorization_code" \ -d "code=***" \ -d "redirect_uri=***"The client ID and secret are set up from a Services ID. The client secret JWT is generated correctly (this is validated, because I do not receive an invalid_client error).Unfortunately, this fails with an invalid_grant error.Of course the identifier of the Services ID (and therefore the client ID) and the identifier of the App ID are entirely different. This is because it's not possible to make a Services ID with the same identifier as the App ID. It is unclear what client ID should be used, or how to make a Services ID for use with data from the native API.The redirect URI parameter is also very unclear - since there is no redirect in the process. However I have found that the result is always the same, regardless of what the parameter is set to (including if it is omitted entirely).I suspect this process is failing because the authorisation code simply wasn't created for the client ID of the Services ID. However there is no way to indicate the intended use on the native API, as far as I can see.I have scoured all the documentation at length and have still not gotten anywhere. What is the intended approach to take an authorization code from ASAuthorizationAppleIDCredential and exchange it with the REST API?Thanks!