@hetzer

1. Turn M5StickC off
2. Remove USB C from M5StickC. (If plugged.)
3. Connect BAT and GND pins together with a jumper wire (male to male).
4. Plug USB C into M5StickC and finally ...
5. Remove immediately jumper wire.

Your M5StickC will now work as expected !

Do this every time M5StickC battery is drained because of bad HW design. :-(