PSP won't charge via ac adaptor

[Atari 5200]

I've got a friend's psp slim that won't charge via adaptor. It charges fine via usb, so I shouldn't be the battery, right? I was thinking something may have come unsoldered or something is loose. I used to own it myself and it would charge for me fine, so I don't know if he's doing something wrong or if something happened to it. He's using an off-brand charger, so could that have anything to do with it?

Any feedback is welcome! Thanks!!!

[Mianrtcv]

Some after chargers just don't age well. My cell phone charger for one, a compatible atari charger... That said, it could be thin pin needs re-soldering. Gd luck either way.