"Missed appointment now means missed operation"

I have been awaiting an operation for my veins for a long time. Now my doctor has sent me a letter saying the hospital contacted the surgery and have now cancelled the operation as they said I didn't attend an appointment. The fact that I told them that I didn't get notified of any appointment had no impact on their decision (rudely told to me by the departments secretary at the hospital). My doctors have called the hospital again as they know I'm very upset about it all, but they also were told quite abruptly by the hospital department secretary that I still cant have the operation as I missed the appointment.