WearOS
I was until recently using an Huawei watch that required "WearOS" there were 3 updates in the 9 weeks I used the device and each and every update broke something fundamental. no amount of fiddling / unpairing / re-pairing would make those things work again. Thinking my watch was faulty I had it replaced, twice. nothing, the bog standard, least I expect I expect functionality of a smart watch could not be regained.
a lot of google stuff is excellent at what it does... WearOS is not one of them.