The technician did not treat my back yard.

We always start in the back yard, so if you are home you may not have seen them until they got around to another area.  If you are checking your home security cameras, many motion-sensitive cameras do not catch the motion farther away from the camera, or only record a snapshot and will not record their visit. If you think we were not there, check your invoice to see what we did that day. If we applied a granular fertilizer you should be able to look into the grass and see the product on the ground.