Unfair treatment of customer

I joined The Gym company on 01/02/2015 and was assisted by a representative named Bheki Moyo who advised that even though it stated that it's a 3 year contract, I could cancel anytime. Unfortunately I lost my job on 25/07/2015 and I advised the Gym company that I'd like to terminate my membership. Sue Madonsela advised that I should pay the arrears and sent a letter of termination, which I did. Then a white guy called saying I need to pay termination fees and I explained my situation but he just threatened to blacklist me. I cannot have that happen to me as I am in the job market and that would affect me negatively. I then followed up with Sue to find out how much I need to pay to be released from the contract and to date she has not rep**** but I am still being harrassed by the gym company saying my account is in arrears? How when I told them of my intention to terminate my membership? I have sent email after email asking for their advice in the matter but to date there has been no response. I must say I rergret ever taking this contrct. Id never advise any1 to join this gym. They are happy to take money but don't service clients well. I can't relax on this. I cant be blacklisted