Hi Bill Carpenter Jr - EGP I want to help you with this question.
To remove a greyed-out account on the MS Authenticator app, you must delete the account from the smartphone. Consider creating a backup of the MS authenticator settings before you test the following.
You have to edit your smartphone parameters (it differs depending on the manufacturer or model where you can find the account settings.
If you found the settings, you should see an entry "professional account" (or something) foo@bar.com
Delete this account
Return to the MS Authenticator app and the greyed-out account should be gone
I hope this will help you to solve the problem
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