Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Thanks Malcolm.
Any chance your device can support updating OS to at least 12?
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. 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
If your device cannot update its OS to at least 12, your options will be: Use the web version or an alternative like LibreOffice might still work. And you want to cancel your subscriptions, unless you want to use it on a Windows device, or mac device running OS 12 and above.