The tumblers in the lock cylinder are sticking causing the issue. They are made of softer metal so after a few thousand times of having a key shoved in them, the tumblers bend alittle causing the issue. Remove the covers, turn the ignition to run. On the bottom side of the cylinder is the retainer, it is spring loaded and can only be pushed in with the key in the on position. Push in the retainer and remove the cylinder. Turn the cylinder to the accessory position and the stop on top will come up against one of the brass pins. Pull the pin down and continue to turn it and the inside cylinder will come out. You will now be able to remove the tumbers. There is a spring under each one, don't lose it. Remove one at a time and file them down flat and reinstall them.