Account Detected Error with Warcraft Rumble

The battle.net login says "Account Detected - Switch Accounts to Continue Playing" but when I switch accounts to my main account, it fails.

Login with my Battle.net Email fails

If you entered your email and password and you receive an error:

Make sure that you are entering the correct information, without any additional spaces or characters. If you have your login details saved on your device, try typing them in manually.
If you tried to log in using third party credentials like (Facebook, Google, Apple ID, etc.), you will need to first log in with those accounts successfully before you can use your Battle.net email login.
If you are on an Android device, make sure Chrome is your default browser
Try reset your Battle.net account password
Delete app backup from Google Drive: Open Drive app, tap menu, tap Backups, select device, select the game you are having trouble with in App Data, tap delete.

If the problem continues, you may be experiencing a technical issue. Please check our Warcraft Rumble Connection Issues article.