Please check if the adaptor is connecting correctly, and make sure the battery is not defective. If it is inserted incorrectly or the battery is defective, the LCD will show “ ’. Please check if the battery pack is not too hot/cool because of Hot/Cold delay will stop the battery charging normally while the LCD is indicating “ ”. You may put the battery pack in room temperature for cooling/heating and keep charging between 4℃ and 40℃. If still can’t charge battery pack, please take (TOUGH SYSTEM MUSIC + CHARGER) to an authorized service agent.