I have a Flutter Android app that uses Firebase Authentication. It was working fine with the old Firebase project. After switching to a new laptop machine to run project on different device I get the following error when trying to send OTP even after adding the SHA-1 and SHA-256 key on firebase for that device:

This app is not authorized to use Firebase Authentication. Please verify that the correct package name and SHA-1 are configured in the Firebase Console. [App validation failed]

Here’s what I’ve done so far:

Added the package name and SHA-1, SHA-256 keys to the Firebase Console.
Enabled Phone Authentication in Sign-In methods.
Enabled Play Integrity API.
Downloaded the new google-services.json and placed it in the android/app directory.
Verified the package name and SHA keys multiple times.
Additional Info:

My app is not on the Play Store. I’m testing it directly from Android Studio.
Created a brand new app and implemented Firebase Auth, but still facing the same issue.

Steps I’ve Tried:

Verified the package name and SHA keys multiple times.
Ensured the correct placement of google-services.json.
Updated Firebase dependencies.
Cleaned and rebuilt the project.
Checked Logcat for errors.
What else could I be missing? Any help is appreciated.