Try to change the charger, if it can't be charged, maybe the battery is broken. Or maybe the power bank circuit is faulty. When the charging bank is output and the charger is input to charge, there may be a fault and the charging bank is broken. Disassemble the power bank, disconnect the battery, reconnect the battery, and try the input charge. Or after the battery is full, connect the charging bank, and then enter the charge activation.
You can also change the battery to try, if the battery can not be used, it is the charging treasure is broken.