Spotlight Cam Pro gets "tired" by motions that do not trigger a notification

I've bought the Spotlight Cam Pro specifically for the radar based motion detection, because in my cameras view there is a street and a sidewalk, which should not trigger motion. However, I run into the issue that motion is only triggered inconsistently. It does have nearly no false alarms, so ruling out pedestrians on the side walk or cars on the street does work. However, it feels like it still recognizes these and just does not notify me which leads to the motion detection being shut off after a pedestrian walks by (I believe for energy saving purposes). I've tested this numerous times and this seems to be the issue. So when someone enters my property shortly after someone else has just passed by, the camera often does not record anything. Has anyone else had this issue? Is my device faulty or is it a general problem? I'd appreciate your help. Thank you!