Adding our case with the same confirmed server-side signature. Feedback Assistant: FB24587131 App ID resource ID: GUYR4794T9 (The app name and bundle identifier are intentionally omitted from this public reply; full identifiers are included in the Feedback report.) The native Sign in with Apple sheet appears normally and Face ID succeeds, but it then shows “Sign Up Not Completed.” No credential is returned, and no request reaches our backend. The attached sysdiagnose confirms: AKSQLError Code=-6003: “No applications were found with the provided Client ID” AppleIDAuthSupport Code=2: “M2 missing” AKAuthenticationServerError Code=-24000 APPLE_ID_AUTH with PRIMARY_APP_CONSENT, the signed binary entitlement, and the embedded provisioning profile have all been verified. Could an Apple DTS engineer please inspect and re-provision the server-side Sign in with Apple registration for this App ID? Thank you.

Same issue and the same server-side signature on a new, unreleased App ID. App ID resource ID: GUYR4794T9 (The app name and bundle identifier are intentionally omitted from this public post. I can provide them privately to Apple.) The native Sign in with Apple sheet appears normally and Face ID succeeds, but it then shows “Sign Up Not Completed.” No credential is returned, and no request reaches our backend. A device sysdiagnose shows AKSQLError -6003 (“No applications were found with the provided Client ID”), followed by AppleIDAuthSupport Code 2 (“M2 missing”) and AKAuthenticationServerError -24000. The App Store Connect API reports APPLE_ID_AUTH with PRIMARY_APP_CONSENT. The signed TestFlight binary and embedded provisioning profile both contain com.apple.developer.applesignin = ["Default"]. Could an Apple DTS engineer please inspect and re-provision the server-side Sign in with Apple registration for App ID resource ID GUYR4794T9? I can provide the Team ID, full sysdiagnose, and exact reproduction timestamps privately.