Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Thanks Deepa,
The net start schedule was running
So I uninstalled as suggested.
Installed again (under original account) and the 'unauthorised' message has gone.
If it comes back again in a few weeks time, I will do again but installing under a new account.
Thank you very much for your help,
Mike