The door has slipped on it's axle and it was originally "crimped" on. The right way to do it would be replace it and if I remember correctly the chassis has to be split so it's a pretty major job.
The joint I used to work for had us try to squeeze the door tight to the shaft with pliers.
If I were to do this on my own camera(don't have a 'blad) I would
1) open the doors
2) mix some slow cure epoxy and apply it to the ends of the door where you can see the shaft.
If you go this route, apply no more than a pinhead size drop to each end of the door and keep it away from the pivots.
press the door flat against the roof of the mirror box and let it dry for the full 24 hours.
3) Then send it to the guy you should have in the first place to repair your repair.