I have watchOs 2 beta 2 installed. I had the same problem most of the day yesterday and this morning. Had a Genius appointment today. While waiting for the appointment I was trying on other watches at the store and the guy helping me with that was asking about the problem I was having, so I was showing him what was going on and it was now going farther than it had been. So we just sat there and watched it until it finally finished whatever it was doing and went to the language then pairing screen and I was able to pair it again. Had it fixed before my appointment time. Can't remember how many times I had to reset it, but it was at least a dozen.