I also have the same problem , but what i did with mine is that i disconnected the battery and "tada" i never experienced the restart again , might be battery calibration issue with bms , just make sure to clean the battery terminals before putting it back
i also use an app called "BatteryBot" , the voltage of the battery of mine is 3.09v when on 15% , normally it should be between 3.5 to 3.4v , it might be possible that the battery is almost ready to give up as the same as its happening to yours
I know its not a permanent solution
But replugging the battery should temporarily fix it :)