Dear Nordic Engineers
Our customers use nrf5 sdk 17.1.0 for development, and they now test and find that they use the ble_app_keyboard example to connect, and there is a problem of disconnection after the mobile phone is connected to the device.
Their phone model: Redmi k30i 5G
Mobile system: Android 11
APP for testing: nrf connect
The specific phenomenon is that after the mobile phone is successfully connected to the device, after a period of time, the mobile phone will be disconnected. I have used other Android phone tests and did not find this phenomenon.
The following is the LOG printed by the nrf connect app

Please help me analyze what is causing this phenomenon.
Best regards.