@law23805 attach an ammeter to it and see if your power bank still pulls a charge. If it does not check the charge connector and make sure there are no bend/broken pins, no corrosion and no debris in it. You can clean it will a few drops of isopropyl alcohol and a few puffs of air-in-a-can. If that does not resolve it, time to open it up and take a look at the charge controller board etc. and post some good pictures of what you find. Everything will be a guess until we see what is going on with it,
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