Incorrect device name on M4 Pro Mac mini after migration

I've just received my M4 Pro Mac mini and have migrated everything from my M1 Air via a TimeMachine backup. Everything has worked well apart from the name which now shows my M4 Pro Mac mini as M1 Air. I have changed the name via settings/about - and it now appears there correctly, however, if I click on Apple Account in Settings, my device still shows as M1 Air. If I log into my apple account online to manage my devices, it also shows my Mini as M1 Air. I have read numerous posts about restarting the Mac 2 times, but this also hasn't worked. What am I missing? How do I change my device name?

[Edited by Moderator]