I have found a couple of times the time frozen when i flipped my wrist to check time. Both times it was two hours late!. Then i pressed the display with my finger and the time was right again. I am not using any kind of battery saving mode. Battery was at 90 percent charge. It is the second severe failure i have found since i own the watch, two weeks ago!. The other one was the watch turning off for no apparent reason. Apple support has recommended to unpair the watch and pair it again. Apparently they hope wipping the watch could fix anything but i am not so positive. I have found the failures with firmware 3.1.3 installed.