Pull the garage door down.
Locate the lock bar guide bracket on the right side of the door. This should be an L-bracket that holds the bar in place on the door near the track.
Loosen the screws that secure the bracket to the door. Slide the bracket up or down slightly until the bar inserts smoothly into the track slot.
Tighten the screws once the bracket alignment is correct.
Repeat the process on the left side of the garage door to align the bracket.
Turn the handle on the door to test the adjustment. With the guides aligned properly, the locking bar should pivot smoothly allowing the handle to turn.