A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Hello, thank you for reaching out to Microsoft Q&A.
If the Office apps are in read-only mode, it means that your license is not being recognized by the system. In this situation, first check your Microsoft account's Services & Subscriptions page to see if the product key is linked to your Microsoft account.
https://account.microsoft.com/services
If you see your license there, you can use the Office License Removal Tool to remove all previous traces of the Office license and then reactivate it using your Microsoft account. See,
How to remove Office license files on a Mac
Let me know if you still need more help.