I bought a Rolleiflex SLX from Adorama several weeks ago and it had been working fine. However, today I loaded a roll of 120 film and when I released the shutter to advance the film to frame 1, it ran the entire roll through to the end without any advance in the counter. (For those who are unaware, this camera has motorized film advance.) So I got an old expired roll of film and tried again. This time the camera advanced one frame, but not to the start of the film. So I pressed it again, and again it advanced only one frame. It's supposed to advance to frame 1 of the film, then you're ready to start shooting photos. I've ensured the camera is set for 120 film. I've tried with two different film holders and get the same problem; one release is one frame and the counter does not count. Any ideas?