According to your description, I have 2 questions as following.
- Is your Office activated successfully?
- Where did you log in to your account? For example, under User Information, under Connected Services or others.
Please choose one Office app, go to File > Account, take a screenshot of this interface. (Please also note, cover your personal information to protect your privacy, such as the email address, as the forum is a public place.)
I would suggest you perform a Repair Online for Office first.
In addition, please quit or close any security software temporarily to check this issue.
If they all do not work, please uninstall it compelety and reinstall Microsoft 365 apps.
Any updates or questions, please let me know.
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