These common steps are recommended to perform for any issue faced with the backend

Ensure you have added the following cloud permissions for firebase@flutterflow.io: Editor, Cloud Functions Admin, and Service Account User. Here are instructions on how to do this. Update your Firebase rules. Here are instructions on how to do this. Ensure all the data field types and names match in Firestore and FlutterFlow. Here are instructions on how to do this. If you have already completed the Firebase setup, remove the existing permissions and complete a new setup from scratch. Here are instructions on how to do this. Make sure you've added app.flutterflow.io to Authorized Domains under the authentication tab in Firebase. Ensure you are on the latest version of FlutterFlow by selecting (ctrl/cmd + R). After you have done this, clear your browser cache and log out/into FlutterFlow. To use Cloud Functions like Push Notifications, Payments, etc. Please make sure your Firebase project is on a Blaze Plan.