Hi,
Two weeks ago something weird happened to my vivoactive 4. It started to switch off during activity. Works well in "normal" usage, connects to GPS while preparing to Run but after few minutes of running it's just switching off. Moreover I can't turn it on because there is only Garnin triangle logo and black screen. When I got back home and connect it to the charger it turning on normally and my last activity is paused in the moment that watch turned off.
I did reset to defaults, disabled heart rate monitor and problem still occurs.
Software 6.90
GPS 5.40
ANT/BLE/BT 8.02
TSC 2.05
Sensor 18.02
WHR 5.0