Why doesn't the battery level update in the APP after charging the Xiaomi Smart Doorbell 3S?

For your reference, here is the display principle of the battery power of the Xiaomi Smart Doorbell 3S in the APP:
1. The doorbell obtains the battery voltage, converts it into the number or percentage of electricity, and then displays it in the APP;
2. The power display is not real-time. The doorbell needs to be online to transmit the data to the cloud, which feeds back to the Mi Home/Xiaomi Home APP for display;
3. If the network or the power consumption is abnormal in a short time, the APP cannot accurately obtain the doorbell synchronization data.
After charging, you can press the doorbell several times. After the doorbell is connected to the network and the power information is transferred to the cloud, refresh the Mi Home/Xiaomi Home APP, and the APP can quickly display the battery power of the doorbell.