We trust that you are using a wall charger with an output of 5 volts and 1-2 amps, used the supplied USB cable and it works on other devices, not just your unit. If this is so, it could be due to your card, which may have affected your device functionality. 

To resolve this, please format your card using an SD card adapter. You can follow the video instructions on this link here. If you have a newer model and it has a reset button, perform a master reset after inserting the unit back. Then try to charge it again and check if the charge light is now turning on indicating the unit is taking charge.

Note: You can also try charging without an SD card and see if this helps.