If it was serviced by Omega and its subsequently developed an obvious fault within 2 years I’d expect them to sort that out FOC on a goodwill basis. When you say it ‘stopped winding’ I don’t know what you mean, but clearly there’s a problem. If the winder us turning and doesn’t stop turning the mainspring has broken. If the crown won’t turn there’s a fault with the keyless work and that reflects on the previous work in my opinion.
Unless the watch has been ill- treated it shouldn’t give problems after a couple of years.