What is wrong with my Sanyo Xacti Camera?

The Camera (Sanyo Xacti) was working fine for a couple of months until one day, in the middle of using it, it said it was running out of battery, I plugged it into charge and although the red light went on to 'confirm' it was charging, it wouldn't turn on like it's supposed to be able to do while charging. Even after charging it for the recommended time it still wouldn't turn on. I took it to a electronic shop and they told me there was nothing wrong with the internal battery, or the charger, but he wasn't a camera expert so couldn't specify what was wrong with the camera iself. Does anyone have any ideas about what the problem could be?