This usually means Office is not recognizing the active Microsoft 365 subscription on the current app installation, even if the payment already went through. When that happens, Office can go into reduced functionality mode, where documents can be opened and printed but not edited or created.
Try this in order:
- Close all Office apps.
- Open Word again and sign out of every account shown in File > Account.
- Close Word, reopen it, and sign in with the exact Microsoft account that owns the Microsoft 365 subscription.
- In File > Account, check that the subscription is associated with the correct account.
- Go to the Services & subscriptions page and confirm the Microsoft 365 subscription is active.
- If the subscription is active but Word still shows the yellow bar, go to the Payment options page and make sure the payment method does not show an error.
- If the payment and subscription both look correct, restart Word and try editing again.
If the issue started after renewing, signing out and signing back in often forces Office to recognize the renewed license again.
If Word still will not allow editing, reinstall Office from the Microsoft account Services & subscriptions page so the installed apps are linked to the correct subscription.
For immediate access to documents while fixing the desktop app, Office on the web can be used at Office.com.