"Why won’t my watch pair after screen replacement?"에 답변I also had the problem, that my Apple Watch did not pair, after replacing the screen. But it was very strange, since the watch did pair at first. Then I was not able to add my credit card via Apple Pay or update to wOS 5.2.1 (from 5.2) and so I unpaired the watch, hoping that it would work once pairing it again. Unfortunately it would not pair again at all. So I opened it after reading this thread and figured out, that the GPS modules connector was loose and just fell of the display, when I touched the cable. So connecting the (not working) display from another watch made it pair and upgrade again but still I am not able to add Apple Pay. I guess that it recognises the GPS module and since it is wOS 5 it works even though it is not the original GPS module. But I think, because it is not properly connected to all three cables of the display the GPS maybe is not able to fix a location which disables the Apple Pay function out of security or licensing reasons.