Thanks a lot for the advice.
I've adjusted with allen key at the top and it has improved it slightly.
I'm in the process of sourcing a new cylinder lock and handle as they are both old and worn.
I'm hoping this will help as well.
I've just moved into a house with a upvc double glazed front door. It has the catch in the middle where the lock/handle is and a bar at the top of the door and a bar at the bottom of the door.
The bar at the top of the door is getting stuck in its slot when the door is closed so when i try...