Although you see your name at the top of the Word document, sometimes you need to sign out and sign back in for Microsoft 365 to recognize the active add-ins.
To sign out, click on your name and select Office user info from the drop-down:
Under the Account - User Information section, click on Sign Out:
Confirm you want to sign out by choosing Yes and make sure that you have all other Microsoft applications closed (Excel, Word, Outlook, PowerPoint, etc.):
To sign back in to Microsoft 365 through Word, open a blank Word document and Sign In at the top of the document:
Enter your work email address/Microsoft 365 login and password on the next screens, and Sign In: