How to upgrade my iPhone from iOS 15.7 to iOS 16?
How do I upgrade from iOS 15.7 to iOS 16?
[Re-Titled by Moderator]
Bearing in mind that only iPhone model 8 or later can install iOS 16, if your unidentified model supports that version but you can't update, you might have used iOS Beta versions. Should be this case, you need to delete the beta profile in Settings > General > VPN & Profile Management, restart your iPhone, then check for updates again.
Regards
Giulio