The editing features in Office are unavailable because the Office license is missing for this device.
In some cases, restarting Office will fix the problem. You can also try updating Office as described in Install Office updates.
If you still can't edit after restarting and updating Office, please contact your admin or help desk to troubleshoot this issue. Your admin needs to verify that the device-based subscription settings in Azure AD are configured correctly using the guidance in Device-based licensing for Microsoft 365 Apps for Education customers.
Known issue
We’ve identified an issue where some customers are incorrectly seeing this error message. The fix was available in an update that was released on Tuesday September 10, 2019.