Options : a) hard reset b) restore with iTunes.

Hard Reset ..

Hard Reset.

Prior to iOS 15 it used to work, from watch to phone & vice versa, had a case opened with Apple care at the time , support agent did a diagnosis of the watch & phone only to come to the following conclusion “software glitch” which he later informed that would be taken care of on the next update ; we are at 16.1 now ; still waiting.