A family of Microsoft word processing software products for creating web, email, and print documents.
Hello,
If your OS is above version 12 but below 14, your office products can be functional, but Microsoft no longer maintains or updates that version. In this scenario, you can install the older downgraded version.
However, if your macOS is below 12, Office products will now enter reduced functionality mode. In other words, the OS is too old to receive the licensing update the Office now requires. Downgrading to version 16.66 is not going to help resolve this issue either. The downgrade option is only for macOS between 12 and 14. Sorry
This is an update that occured on July 13th and Microsoft shared it here: https://support.microsoft.com/office/update-microsoft-365-or-office-on-your-macos-or-ios-device-f418ae5d-bb5f-4078-b3d9-9340f5dd084e?apid=ets
If your device cannot update its OS to at least 12, your options will be: Use the web version or an alternative like LibreOffice. And you want to cancel your subscriptions.