Automatic seatbelts are not cool!

This is a simple problem which further lets me understand why automatic seatbelts flopped. My passenger seatbelt will not move...it stays forever locked towards the back. I sometimes hear the seatbelt try to move forward once I open my door..but it doesnt move. it stays locked in one place. i tried lubing the thing and that didnt work. is there a way I can fix this thing without having to go to a body shop to get it fixed. it lookes like it would be easy. i just dont want to touch it and break it even more. Any ideas??? Thanks