ALL MY PHONE DOES IS FLASH LG
Try going into the stock recovery and then plugging in the charger. To get into the stock recovery: Pull battery. Hold power button for 30 sec to clear the phone. Hold home + volume down button, then power button (All at the same time) until you see your android recovery screen. Then plug phone into charger for 30min. Unplug charger, then select reboot system. Once rebooted finish charging.
If this doesn't work then you could have a defective battery, cable, or wall plug end.