Our 2003 cab bonnet release handle has been getting harder and harder to pull until last week and, BANG, the pull handle itself snapped (car is on 120k miles). got the bonnet open and have a new pull handle to fit this weekend. but, my makeshift pull of a cable tie wrapped around pliers to pull, it still needs someone else to push down on the front of the bonnet to release it

Any ideas?

cleaned the mechanism up loads with WD40, triggered it loads of times manually to try and free it up. Is this a common fault, and how do i rectify it please?