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Sign out of Office by clicking Word/Excel/whichever Office app you have open, and clicking Sign Out:
Open a web browser and go to https://portal.office.com.Click My Account in the upper right corner (may be a circle with your initials):
Click View account.
Click Office apps.
Click Apps & devices.
Click on the little downward arrow next to Devices in the Office section:
Find the device that most closely matches the name of your Mac and click Sign Out next to it, if applicable. (If it isn’t here, that means it updated correctly when you clicked Sign Out on your Mac).
(microsoft.com) and log in with your OTC email address and password.
Select the device name that represents your Mac device and click Disable lost device.
Return to Office and Sign In. Enter your OTC email address and password if prompted.
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