Apple Pay Won’t add a card on Apple Watch

I hope someone can help with this. My Apple Watch will not add any cards to Apple Pay despite working fine to begin with. Unfortunately I had to reset my watch due to a data issue (which has since been resolved) and now it won’t add any cards.

The cards are showing on my phone and work perfectly. I’ve used Apple Pay numerous times this week and both banks say there is no problem at their end. You can see the “Add” icon in the Apple Watch app, however when you click add the timer spins round for a few seconds before displaying either “Apple Pay temporarily unavailable” or “could not add card, please try again later or contact your card issuer” messages.

I’ve done the usual restarts on both iPhone 7 and Apple Watch. I’m running latest iOS on both devices. I’ve signed out of iCloud and back in again. I’ve restored both phone and watch. I’ve changed the pin to a longer pin rather than simple. I’ve removed the cards and re added them. I’ve also tried to add the card manually. Everything I’ve tried has failed and I can’t see anything else online which will help!