Only powering on with charger
I’ve recently bought a 3DS. It can only work when the charger is plugged in. The charger can charge the battery (I’ve checked with a multimeter and a spare battery). When I unplug the charger the device shuts off. 3DS also automatically powers on when I plug the charger cable. I checked the power button but when the device is open it functions properly. I haven’t found any postings with similar issue. What can be the cause of this?