12.000mAH Power supply not working after 3 months.

Problem with Plugable 12,000mAh Ultra High Capacity Portable Dual Port USB:
When I plug my phone into the 2.1A USB port and press the button on the side, the rightmost LED blinks rapidly, about 9 times, then stops. There is no indication on my phone that it is charging.(By ‘rightmost’, I mean that I am holding the charger so that the ‘plugable’ label is readable, and is not upside down.)
When I plug the USB cable into the charger’s input, the rightmost LED blinks, then the next one over blinks, etc., until the last one is finished. Within 6 minutes, all LEDs are solid, but I cannot charge anything with it. When I reconnect the USB to the charger input again, it starts from LED #1 again.
I think it is defective. How do I get this issue resolved?