Hi, I have one of these loft hatches with the lock where you just push the hatch up to close and it fastens or you push it up further to open. Unfortunately, it doesn't now seem to work and I can't get it open however much I try to push the hatch up, it will only go up about half an inch and the lock doesn't free. Has anyone had this problem and any idea how I can get into the loft again please? Many thanks for any help.