Spotlight Cam Battery - Cannot edit motion zones

So I just received my new spotlight cam and all installed and setup fine. During the motion zone setup I selected an area just to test it. I now want to amend the zone and bring it down slightly so the road is not covered, however I only have the option to disable 3 different sections of the existing zone, and I don't have the ability to change where it covers. Now everytime a car drives past it triggers the camera which is not what I want. Any help would be appreciated!