It seems my film back is not locking correctly to my camera body, if I pick up my camera by the film back the two can become quickly seperated for a dropping accident! It appears when I attach the film back to the camera the lock botton on top of the magazine does not return to the left far enough leaving the magazine ready to fall off. Is this a problem anyone else has experienced before? My camera is the 203fe and the back is the E-12-6X6. Thanks in advance!