I checked on the MS website and found this recent link which might provide you some useful information: https://answers.microsoft.com/en-us/windows/forum/windows_10-update/notification-that-my-version-of-windows-10-is/caea86a1-8fb1-45e5-9980-02c5e158d8a6
(Note: In that chain you will see mentions of W10 update problems, mine included. Kim has done articles recently on W10 update problems. I have experienced some of them.)
If your W10 version matches the situation described in the article, the notice could be valid. If you choose to update, your running system – Windows 10 >> All Settings >> Update & Security >> Check for Updates should advise you what your running systems thinks about your need to update.
As always, your mileage may vary.
Take care, stay well,
don