Users in my FlutterFlow app keep hitting a “Not Authorized” message the moment they try to sign in by phone. No other Firebase services are complaining and I haven’t touched any Firebase or GCP settings myself, so the problem is isolated to Phone Authentication. I can’t share the FlutterFlow editor, but I will grant you full-editor rights in both Firebase Console and the linked Google Cloud project (IAM). From there I need you to: • Audit the current SHA-1 / SHA-256 fingerprints registered in Firebase and Google Cloud. • Review and correct any API restrictions—especially Identity Toolkit—so the phone auth endpoint is reachable. • Confirm Authorized Domains and OAuth consent screen settings are valid. • Make sure the backend handshake between Firebase Auth and the Cloud project is wired correctly, eliminating the “Not Authorized” response. Acceptance criteria 1. Phone number sign-in completes successfully on a test build I provide. 2. No other enabled auth methods or Firebase services are broken in the process. 3. A brief summary of the exact changes you made (for future reference). If you are comfortable resolving this strictly through Firebase and GCP without FlutterFlow access, please let me know your approach and estimated turnaround.