My daughter recently purchased a 760 and a strange thing just started with the power locks. When inserting the key into the drivers door lock the key will not turn either way. The passenger door lock still works (fortunately) or you wouldn't be able to get in the car. Once in the car, you pull up on the drivers side door lock knob and all door lock open. To lock the car from the drivers side, you have to open the rear drivers side passenger door, reach over and push down trhe lock knob on the drivers door, and the locks will engage. Can anybody help? Why won't the drivers side door lock turn?

Thanks for your help.
,Randy