Mine has the same problem...I think its a broke spring that releases the lock. Thais what my father in law told me. I dun know I just haven't worried about it .....it closes fine. It does need a lil push to open. Try to grease the tracks really good that might help as well. Look for a spring on both sides if one is there and other isnt...thas your problem. You should see 2 springs on either side in the tracks.