Central locking fault?

[Alli8]

I've a little problem with my IQ(1).  The passenger door central locking doesn't work and I have to manually lock/unlock the door from inside the car.  The car has had a repair to the passenger door so I know it has been off.  The power window also did a weird thing in that it wouldn't auto-close but thanks to this forum I discovered it just needed a reset and works fine now.

I'm wondering if whoever refitted the passenger door forgot to plug something in... could it be as simple as that or like the window, does it maybe need resetting to the fob (if that is even a thing) or could I be looking at something more costly like a motor?  Is there any way to tell that doesn't involve taking it to a garage??

Thank you

[Vscudetto]

Either unplugged or door lock has failed.