Lock Assmebly, help, locked out!

On my driver’s side, the key doesn’t unlock the door.

It seems like there is a broken piece that prevents it from unlocking. I greased it up, but I don’t know what to do to fix it.

If anyone has any ideas, please, please help me, I’m selling the car, and I need for people to be able to unlock the driver’s side door!

u can get a lock cylinder from the deal. and pull the door panel off n see wat came loose.

how much do you think a lock cylinder would run?

also, would this replace my current key? could i just pick up a lock cylinder off a junked car?