Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Hii,
What version of MacOS are you using?
In this case, try uninstalling your current version of Office.
Access the App Store and check for updates; wait for the process to finish.
Access the link below and download the latest Office Mac package.
https://www.microsoft.com/en-us/microsoft-365/download-office
After installation, look for Microsoft AutoUpdate, check for any pending updates, and wait for the Office software to update and launch.
Log in with the Microsoft account that has the Office license.
Thanks