Problem with exercise and stand rings

Hi - for several months and on random days at random times of those days, my stand and exercise rings suddenly close, filling all the way back to midnight. My activity ring is not affected.

I have factory reset my phone and watch without resolution. I have an Apple 3 watch. Thoughts on another step I can take?

It’s incredibly frustrating and makes fitness and health tracking pointless (this data makes my average exercise over the last several months an unhealthy huge number).

Thanks in advance!