Huawei WATCH 2 Faq page 4

Check whether Package Installer or Android System is at the top of the Wear

OS by Google app power consumption list. If so, it could be that the rapid
power consumption is caused by a rare software issue. Please restart the
watch to fix the issue. Please also update your watch's software at the next
available version release, as this will also fix such issues.
(2) Check whether the watch has undergone heavy use. The watch's standby
time will be reduced in respect to how much it is used. The following
situations may result in reduced battery life:
Prolonged use of the watch to play music or make calls.

Prolonged use of an exercise or map navigation app.

Prolonged use of power-intensive third-party apps, such as Google Fit or

Runtastic.
Frequent message notifications.

3. For the 4G version (with a SIM card inserted): If the standby time is less
than 1 day, in addition to the above, please also check the following:
(1) Check whether the watch is disconnected from the phone. If Bluetooth is
disabled on the phone or watch, using the watch's independent connectivity
functions will result in higher power consumption than usual.