We built a house 7 years ago and have a garage door with a lever knob.  The lever knob started sticking when we tried to open the door and this started a couple of years ago.  We thought replacing the door handle would be an easy fix, but that handle started doing the same thing.  We had a handyman come out and spray the parts with WD 40, and add longer screws to the hinge of the door. He said something about the screws they used were not long enough. He only replaced some. It seemed better but started sticking again.  We had a handyman come out yesterday and remove the handle. He sprayed WD40 and added a couple of screws. We have a daughter who pushes the lever all the way down at times, and the thought the screws would help support the internal part of the door.  Seemed better, but sticking again this morning. At this point, not sure if it is coindence of two levers, and try installing a third, or something more with the door itself. There have been a couple of times where it feels like the door "pops" around the hinge area, so wondering if somehow the door is leaning a bit, and this is causing the door to stick. This has only happened occasionally though.