Thanks for contacting us and letting us know your issue.
May I know if you mean the PowerCore+ 26800 with Quick Charge 3.0 as below?
From your information, we are unsure if the indicators didn't light up or the battery cannot be recharged. To confirm the issue, may I bother you to connect the included micro USB cable to the input and one of the output ports at the same time to reset the LED indicators? After that, please use another 5V/2A wall charger to recharge the battery for 13-15 hours or a quick charge wall charger for 8-10 hours to see if the problem persists?
If yes, you can contact us via firstname.lastname@example.org and we will be more than happy to help you out as per the 18-month warranty policy.
Sorry for the inconvenience caused and thanks for your understanding.