I bought a Vivoactive 4s 3 days ago. I am quite surprised that I have to charge my battery TWICE A DAY?! I have turned off the Pulse O2 and calendar but my battery does not even last 12 hours?
press top right hand corner button for 15-20 seconds, it will power off the watch. wait for 10 secs then same button press and release to power on again. sometimes it will help the watch to work normal after charging 100%.