HARASSMENT FROM SAYA / PLANET FITNESS!!

I am very disappointed, frustrated and concerned! I took out a fixed term contract for 24 months with Planet Fitness Hennopspark in Centurion in 2015,which I paid upfront for using my edgars account, this was just over R4500, it was during a special they had running, the payment receipt i recieved was my "contract", which i am sure you can understand, has no ink left on the printed areas as it was a basic "till slip". My contract term ended and I telephonically cancelled my account, this was well over a year ago. I did not receive confirmation there of and automatically believed my contract had been cancelled. i am now being harassed DAILY from SAYA to make payment of R2004.11 I am now being threatened to be listed on the major Credit Bureuas. How am i possibly being charged for fees when my contract was cancelled over a year ago!!