"PowerCore Essential 20000 PD" does not re

Hi,
I had bought “PowerCore Essential 20000 PD” and when I’m trying to recharge it, it does not recharge … only one blue led is blinking for hours !!

Please help …Anker

Please test it with another PD wall charger, such as an Apple 18W/61W/87W USB-C wall charger or Nintendo Switch wall charger, and of course an Anker PD wall charger. If the problem remains, please contact Anker Customer Support at support@anker.com for help.