A8L W12 rear passengers door will not operate
 

Hi folks

Just joined have 2004 A8L W12 6.0L
I seem to have a problem with the rear passengers door.
It will not ope from inside or outside.
It has the power door closing and electronic child locks via the drivers door.
I managed to get it open once with my son trying the handle inside and me trying handle and fob on outside.
When I shut the door I have not been able to open it again.
Put it in my local garage and they tried opening it via the computer but no joy, you car hear the lock operating but nothing happens.
I do not think I can even get the door card off without the door being open as the door lock fits trough it .
I did notice that when the doors are locked the red LED's illuminate on all the doors but when you try to open the rear passengers door from the inside the LED's do not go off, The LED's go off when you try the handle on the drivers passenger side
Anyone any ideas?

thanks in advance
Alan