Hi,

With the charger connected does the tablet indicate that it is charging at all?

Try resetting the tablet by using a straightened out paperclip to press the reset button which is found on the back of the tablet. When you insert the paperclip into the reset hole you will feel a button being pushed. Hold the button down for about 4-5 seconds then release to turn the tablet on

Here is an image that shows where it is located.

(click on image to enlarge for better viewing)