Hello, I have recently bought a ijust s and tried to charge it. When I plug it in the red light turns on and a white light flashes. Then after around 10 mins the red light just shuts off. I'll unplug it then plug it back in and then it does the same red light on and white flashes. I am using a 1a charger and the cord it came with. I have tried charging with the tank on and off and nothing is working. PLZ HELP