This may be due to something blocking your garage door sensors. These sensors are located at the base of your garage door. If the sensors can't see each other, the door won't close. This keeps it from closing on any people, pets, or possessions. Try clearing away any dust or dirt from the sensors and make sure they're aligned properly and that nothing's in the way. If this still doesn't work, give us a call and we'll inspect your garage door and opener.