Sky City Sports and Fitness Club

I was told after my contract I will move to a month to month, now because I want to cancel my gym they want a 3-month notice from a month-to-month contract and they claim I owe them R200 for the access key/card of which I've paid while joining the gym, now Sonnika Steyn does no longer respond to my emails.

Bad gym to join honestly, What I don't understand is How do I serve a 3-month notice on a month-to-month contract.