Press the reset button. If the hub voice prompts, "Normal link confirmed", it indicates that the hub and the Aqara Motion Sensor are communicating properly. If there is no voice prompt, please move the sensor closer to the hub and try again. If there is still no voice prompt, the sensor might be deleted, or its battery may have run down. Please refer to the user manual for instructions to add the device or replace the battery.
You can test the Aqara Motion Sensor by putting your hand in front of the lens and check the device records (log). The sensor is working properly if the corresponding event has been updated in the log.