There are details for this here: support.microsoft.com/en-us/office/reset-onedrive-34701e00-bf7b-42db-b960-84905399050c
Make sure OneDrive is closed completely. Click on the Finder (Desktop). Open the "Applications" folder. Find OneDrive and right-click on the app icon. Click "Show Package Contents". Locate the "Resources" folder and open it. Find "ResetOneDriveApp.command" or "ResetOneDriveAppStandalone.command" and run it. When this is complete, close the window. Start OneDrive normally and do the initial setup.
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