Microsoft 365 desktop apps don't recognize active 365 account: Say "Product Deactivated"

I have a Microsoft 365 account for many years - fully paid up and active.

I got a new Windows 11 laptop a few months ago and set it up to use the same Microsoft account.

Worked fine until recently, when a banner notice appeared inside all the desktop apps saying...

• "Product Deactivated. On Saturday 14 September 2024, most features of Word/ Excel/ Powerpoint will be disabled"
• Along with a separate a "Sign-in Required" banner
• The account icon has a warning that my account needs to be "Fixed"
• And autosave is disabled (although OneDrive is working fine)

So far, I have:

1. Re-signed into each app multiple times
2. Gone online to verify that my account is active and the new device is correctly registered
3. Uninstalled all Microsoft 365 desktop apps and reinstalled from within my online account
4. Verified that I can use all the apps on my other computer, and online with no problem

But the problem persists.

I assume it might be somehow related to an expired trial version of the software that might have come with the new laptop, but I'm signing in with my active Microsoft 365 account, and have completely reinstalled the apps from that account, which I thought would have fixed the problem, if that was the cause.

I tried to get chat help from Microsoft, or a call back, but neither came through -- Is there a phone number available for Microsoft 365 Family version support?

Any suggestions appreciated.

Thx,

Donal