Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
What platform are you using your Msft 365 on?
If it is Windows, in the Word, Excel apps, for example, go to Files > Accounts, click on Update license, and log in again when prompted. See if that helps.
If it is macOS, uninstall the apps. Then 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Download and run the license removal tool to clear outdated cached license. Then reinstall the apps, and see if it works. For reinstall, if the license is via Microsoft directly, install via https://account.live.com > Subscription, find the personal plan > Manage, and find the install option. If it was via Apple App store, reinstall via the App store.