Fixing A stuck Window Lock

I live in an older apartment building, I have lived here for 10 years now in this unit. That balcony lock in the picture never worked, I thought nothing of it, I did not even know my balcony door had a bottom and a top lock, I did not know that was a top lock mechanism. The slider button never budged when I pushed it up. Last month I decided to play with it and a friend told me it was a lock mechanism for the top part of the door. I decided to spray a bunch of WD-40 on the lock and on top of the door and waited half an hour, then I used a hammer to hit the lock up and the lock pushed upwards. Now it goes up and down smoothly when pushing the top lock. I know this is a simple issue I had, but it just goes to show how useful having a can of WD-40 is around the house, it can help in the little projects or issues that need to be done.