Same signature here. Team ID 4M6ZD86466, primary App ID app.hushling.ios (created 2026-08-08, Sign in with Apple enabled 2026-08-09, still failing 2026-08-20). Native sheet renders fully, user taps Continue, framework returns ASAuthorizationError.canceled (1001) with an empty userInfo - confirmed by walking NSUnderlyingErrorKey in our own ASAuthorizationControllerDelegate rather than through a plugin, so this is the framework's own error and not a wrapper losing detail. Verified: entitlement com.apple.developer.applesignin = ["Default"] in the signed binary and in the embedded provisioning profile; APPLE_ID_AUTH with PRIMARY_APP_CONSENT on the App ID via the App Store Connect API; explicit primary App ID, no wildcard, no grouping. Profile regenerated after enabling, capability removed and re-added via the API (DELETE 204 then POST 201), fresh TestFlight builds - no change. Two physical devices, two independent Apple Accounts that had never signed into this app, and both of those accounts sign in successfully to other teams' apps on those same devices. Feedback ID: FB24435334 (includes sysdiagnose with the Accounts/AuthKit profile installed) Requesting the same server-side team-registration fix that resolved GW7XA5CX69 and FRL3DTJQ62.