Spotlight cam

The security light comes on every 3-5 mins. Stays on for a few seconds(2 to 3) and goes off. No motion recordings, so it is not the camera or camera settings. The motion works perfect. How do i know?. I have another security camera that is permanently recording and also has motion alert, which is activated by the light coming on and off all night. Its been doing this for several days now. Can anyone help Regards Darren