Accidents happen all the time! Many times garage doors are lowered onto obstructions or are bumped by a vehicle, which causes the cables to come unspooled from the drum. When this occurs, the garage door becomes wedged and stuck in the tracks. This prevents the door from moving up or down freely. This is a dangerous situation if you are unfamiliar with the mechanics of a garage door. The spring is under extreme tension and can cause bodily injury. We strongly suggest that you DO NOT try to fix this yourself. Some things are better left to an experienced professional and this is one.