So I’ve had the Anker PowerCore 10000 Portable Charger for a while now and it has been amazing. Lately, however, it does not charge my phone. All the cords I have tried using work perfectly fine. When I plug the cord into the charger, the 4 lights on the charger light up one at a time. I have never seen the lights do this before. What could this mean?
Connect USB cord between input and output and press power button.
If that doesn’t work, then looks like a dud. Email firstname.lastname@example.org with serial number, evidence of purchase, description and all your efforts to find the cause.
Have you cleaned the socket?
Otherwise you should do a reset as @professor mentioned.
Last possibility: contact the support
by this point that power bank gave up it best for you to buy new one or get replacement if it under 18 month or younger