This situation is generally the charging treasure does not charge into the electricity, it is recommended that you change a small charging head to try, or plug in the usb charging board to try, the computer can also, if not, is the quality of the charging treasure has a problem, it is recommended to contact the manufacturer's after-sales customer service to apply for after-sales return or after-sales maintenance service.
This is a problem with the circuit board. WD cleaned it up, the internal battery voltage was originally 3.5V, and then charged it directly with a 4.3V charger. After a day of charging, it is ready to be recharged.