If Xhorse VVDI2 programmer reports that the device battery is lower (image attached):
You can replace battery by yourself or send back to your dealer to replace battery.
Battery type: CR2032
NOTE:
Need to use external supply before and during remove battery. Otherwise if you remove battery, firmware is lost and tool is dead.
Gray positive pole, white negative pole. Do not remove the original battery first. Solder a battery like this, then remove the battery to be replaced and solder the new battery on.
So better send vvdi2 unit back to your dealer to repair.
Then update vvdi2 firmware and software.
www.vvdishop.com