Stopped working yesterday on my galaxy watch 4 and the same happened to two of my friends as well on their wear OS. I have tried and removed the app and reinstalled it with no luck. It gives the error "Your watch can't make contactless payments as it doesn't meet software standards". We are in Australia so please don't reply with the copy and paste comment you have been giving to people reporting the same issue. I wish you confirm you have seen the problem and working on it.