Hmm, I've had an issue like that in the past from two separate causes.
First, do you have a wall charger adapter for it? If you do, see if it'll charge on that. Could be your usb port is loose (had that happen on one of mine from the battery dangling on it)
If not that, it could be the battery post is pressed down too far. The center piece of metal inside the atomizer where you screw on your ce5. You can try gently wiggling it upwards with a paperclip and see if that was it. May not be making contact with the charger but be very careful. I would try a wall charger first and see if it's just the USB. Just about any wall adapter with a usb plug on it will do, like Iphone chargers and such.
Also, just out of curiousity, is it locked? With the 5 click shut-off.