If we assume that the film transport mechanism of the camera is ok, this can happen in high humidity , the film sticks together on the roll. I had this before with one batch of films, first I suspected the camera, but finally , I only found out the reason by opening up ( sacrificing) a new film , and found out , the the film material was almost glued together on the roll. This can happen , according to kodak, in high humidity/high temperature.
