You're pretty much right about how Duo Mobile's backup to Google Drive works — it binds to the Google account you first choose for backup, and there’s no in-app way to switch accounts once set.
Here’s the deal:
Why it happens
When you enable Duo Mobile backups on Android, it uses Google Drive’s app data backup tied to the Google account you select.
Duo Mobile doesn't let you switch accounts inside the app.
Removing Duo’s access from your Google account does not reset the account linked inside the app.
So, even if you unlink on Google’s side, Duo Mobile still thinks it’s tied to the original account.
What can you do?
1. Reinstall Duo Mobile to pick a new backup account
Uninstall Duo Mobile (this removes the app data and backup info).
Reinstall from the Play Store.
When prompted, select the correct Google account for backup.
Warning: This deletes all locally stored Duo data, so make sure you have recovery codes or other 2FA recovery methods ready before uninstalling.
2. Alternative: Use Duo Restore
Duo has a Duo Restore feature that uses Google Drive backup.
Unfortunately, this restore only works from the Google account you initially used.
So switching accounts means reinstalling.
Summary
Scenario Can you change backup account without reinstalling?
Duo Mobile backup Google acct No
Unlink from Google Account Does not affect Duo Mobile internal account binding
Change backup account Only by uninstalling and reinstalling
Recommendations:
Before uninstalling, make sure you have your Duo recovery codes saved somewhere safe.
Inform any services where you use Duo MFA that you may need to re-enroll or use backup codes during the transition.
After reinstalling and linking the correct Google account, set up backups again.
