We made an unpleasant discovery today on our 2013 Clubman. After using the remote to open the rear doors, the bag containing the key was inadvertently loaded into the rear cargo area along with a large dog.
But when we went to retrieve it, we couldn't. The rear doors were inexplicably locked. With the temperature in the car rapidly escalating, we had to smash the side widow out.
Do you have this option in your settings - the manual does say country specific so you may not, but it should prevent what you describe happening in the future