I recently deployed an app to Open Testing channel which has google sign in enabled and uses Firebase to control the user authentication. The authentication worked as expected both in debug build and when I sideloaded the prod apk. But when I downloaded from the playstore, it fails with “No Credentials available” error. The following are the steps I did.

1. Added debug signing keys to Firebase Project
2. Created a local .jks file to sign my prod build.
3. Uploaded the aab build to playstore which has its own App Signing.
4. Noticed the new App Signing page has two keys. Classical Key and Post-quantum cryptography key
5. Copied both and updated the firebase project. Validated whether it is added as credential in Google Cloud Console OAuth Screen.
6. Tried logging in with Google. Got the same error.
7. Downloaded the updated google-services.json file, generated build and published again. Still same error.

Does someone here know a solution for this? I need to fix this asap as the deadline to submit the app for a hackathon is very closer.