My Apple Watch face won't change when I swipe left/right from the edge (series 8). Any ideas?

Tried a reset and made sure the face I want is in my faces on my IPhone. When I swipe, no result. Not the first time it has happened and resolved itself but extremely annoying. Just happens out of the blue. I can go and set the face I want on my phone but why do I keep losing the ability to choose from the watch?