Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Ok, I think it is a bit more clear now that you added more information.
You do indeed have two subscriptions. One you pay Microsoft directly, the other you pay Apple and Apple is the reseller.
If you want to use the one you bought from Microsoft, you install it from MIcrosoft.
If you want to use the subscription you bought from Apple, you install from Apple's App store. So it is possible this whole time you might be using the one you bought from Apple, and since Apple canceled their subscription on their end, your apps now stop working.
Do this.
Uninstall your Office Apps.
Please use the instruction here: https://support.microsoft.com/office/how-to-remove-office-license-files-on-a-mac-b032c0f6-a431-4dad-83a9-6b727c03b193 Download and run the license removal tool to clear any expired license.
Then reinstall from MIcrosoft. Go into your account https://account.live.com > Subscriptions, find the Msft 365 and use the Install option to download the installer, and run it to install it.
Once installed, just sign into your Microsoft account to use them.