Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hello Nick Ingarra, thanks for posting this in the community.
This issue usually appears when Office cannot read or verify your license files. Please check first that your Microsoft 365 subscription is active and that your account has a valid license. Then sign out of all Office apps, close them, and sign in again using the same Microsoft account. If the problem continues, try removing old or corrupted license files by using Microsoft’s License Removal Tool for Mac at https://support.microsoft.com/en-us/office/how-to-remove-office-license-files-on-a-mac-b032c0f6-a431-4dad-83a9-6b727c03b193, then open Word or Excel and try activating again.
Kind regards,
John Oli