If you find one of the door locks stays locked and looks like its not working. Do this.
Sit in the drivers seat and theres a switch on the door to lock and unlock the car.
You may need help from someone if you can not reach the lock thats not working.
On the door thats locked pull the door release handle and lift the lock up hold it there as it trys to pull itself back down, let go of the door handle but keep the lock held up.
Now press the button on the drivers door and watch all the locks lock and unlock , you need to let go of the lock thats not working the same time as all the other locks go down. When done right it will work like all the other locks..
Tested on my golf and my mums car.