Hi @Gerald
I suggest you close and quit all Office apps.
Go to the Finder> Applications> Utilities> Keychain Access> Remove the Identities related to Microsoft Office.
Then download and run the license removal tool.
Reopen OneNote, sign your personal Microsoft account for a check.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.