Upvc door mechanism doesnt work when pulling handle upwards.

Hi all,

I just bought a home with my wife and the rear double doors won't lock.

Gave it a good going over with wd40.

Firstly I noticed that the top bolt was catching on the hole in the frame, so I'll adjust the hinges.

But I also noticed that when I pull the handle up the mechanism barely moves. The more times I pull up the handle the more it moves, whereas moving the handledown resets the mechanism just fine.

Any ideas on what to look for and how to fix it?

Thanks in advance,

Richard