3DS XL shuts off sometimes when closing screen
I have a 3DS XL that's in fairly good condition that I'd like to be able to reuse or resell.
Problem is, after a long period of disuse, when I finally charged the battery, I began noticing problems.
1) The charging light will turn off after a period of charging, I'm pretty sure it's supposed to stay on as long as it's plugged in, at least that's how the New 3DS XL works.
2) More importantly, sometimes, upon closing it, instead of going into sleep mode it will just shut off completely, and needs to be turned on with the power button. I haven't been able to replicate exactly how it's happening.
Does anyone know what could potentially be causing this?