I have a Nikon L120 and it will say "Batteries Exhausted" and turn off. I haven't even used it in a week, turn it on, battery is full bar, go to take a pic and "Batteries Exhausted". It can't mean they're dead because it shows the bar as full battery. And I don't know how they can be "exhausted" because I haven't used it. Does anyone know what's wrong with it?