Lets confirm the ON/OFF switch is working. Please turn OFF your device by sliding the switch up and press the red button. If you get a red or green light that means the switch is not working.
If the switch is working let's charge your device in OFF mode for 24 hrs to a wall power source. After 24 hrs unplug it and turn it ON, run a battery check, confirm is 100% and turn it back OFF.
Monitor the battery behaviour and if after some time the battery level goes down again we can confirm there is an issue with the battery itself so please open a ticket with our support team.