Is not detecting my keypad

this device is neat!!!, well i’ll get straight to the point, i was using the keypad of the gameshell and was working fine, but i charging the device and i was using it, and suddenly the screen was off, i push the power button in order to restart the gameshell but once the device was back on again i tried to use the keypad to play some games and it is not working and i took of the front white case just in case the wire was disconnected but was’t and i do not what i can do to resolve this issue