If you set Optimal Battery Life working mode for your battery camera/doorbell, the camera will perform like this:

• The video clip length is up to 20 seconds. 
• The system automatically adjusts the detection time period to reduce the chances of detecting the same object twice in a short period.

Note: When a camera is working under Optimal Battery Life mode, the camera will set its own trigger interval after a false trigger. The shortest interval is 5 seconds. 

However, this trigger interval can be superimposed in a short period of time. With too many false triggers, the trigger interval of this camera will continue to be superimposed, which can be up to the 1920s. During the trigger interval, any motion in the camera view will not be recorded.

Thus, if your camera misses some motions frequently, please check Working Mode under Power Manager. If the camera is in Optimal Battery Life working mode, please try another working mode.