Windows was recently updated to Win 11 (by accident) and is now fully up-to-date.
A potential contributing factor is that the user has both a personal MS account and a work MS account using the same email address. The personal MS account used to have the family version of Office but no longer as the person is now using their work account version. I suspect there's a flag somewhere that is making Windows thinks the version of office is the wrong version and gets confused.
One other thing that might be relevant. the 'licenced to' screen always thinks it the personal account, even after I've activated the work account.