passenger door not auto locking

[lee_fr200]

for some reason my passenger door on my ibiza fr (57 plate) doesnt always lock, sometimes does but not all the time, and when i lock the doors and then press the lock button for the 2nd time, the drivers door is locked but the passenger door isnt

 

[beezanick]

Could be a faulty solenoid in the locking mechanism of the passenger door?

 

[bogdancristiann]

There is a switch in the door lock that sometimes doesn't work, it will fail completely after some time.
The solution is to change the switch, if you have some skills in order to open the lock, if not, change the lock completely.