Door latch

[a-5 freak]

The other day I backed into a pole at a gas station, with my door open, and now I have to replace my door latch. The reason is because the latch will no longer latch shut. So I go out to a junkyard and buy a door latch and I put it on and... Now the jaws wont open. Is there some sort of trick to get the jaws back to the open position?

THX in advance