1. Charger or charging cable failure: First, please ensure that the charger and charging cable used are working normally. You can try to replace another charger or charging cable to eliminate the fault.
2. Poor battery health: If the battery is in poor health, it may not be fully charged. Check the battery for any damage or abnormality. If the battery is aging or used for a long time, it is recommended to replace it with a new one.
3. Charging connection problem: Please ensure that the charger and battery are connected correctly, and the charger is connected to the power supply. Check whether the connection port is clean and free of any dirt or impurities. If the charging connector is damaged or deformed, it may cause charging problems.
4. Other circuit failures: In addition to the above, there are other possible circuit failures, such as battery management system or circuit board failure. If the above situation is ruled out, it is recommended to report the problem to professional technicians for diagnosis and maintenance.
In short, it is impossible to accurately determine the specific cause of the problem. It is recommended to carefully check the above aspects and carry out corresponding maintenance or replacement as needed. If the problem still exists, it is recommended to consult a professional for more accurate advice.