The camera and light motion detection are completely independent of each other (which is bizarre - clearly the camera should trigger the light but it doesn’t). Only upside is that the camera has night vision so still get something - though camera with light turning on is always best.
The light motion detection tends to be a wider area and more sentive than the camera. I suggest you turn it down slightly. Both these sensors are VERY trial and error. I initially put them all on max then slowly tweaked them (reduced sensitivity or area of coverage) each day. Tweak a little, watch it for a couple of days, tweak a little, etc… After about a week of tweaking I got them just right.
Hope this helps