1. Some power banks do not work with Bluetooth headphones. The battery capacity of the Bluetooth headset is small, the general charging current is also small, lower than the current protection range of the mobile movie, the charging treasure will think that the headset is full, it will not enter the charging state.
2. The charger is damaged (and other Bluetooth charger can be borrowed to try).
3. The small battery in the Bluetooth is dormant or broken. (Can be disassembled with a regulated power supply to try to activate)