24 month contract

I got into a contract with Zone Fitness in December on a 24 month contract. I recently got retrenched and went to the Green point branch to speak to the Sales Manager about cancelling my contract as I am not able to pay and being unemployed is ground to cancel a service contract. The manager told me I should have taken a shorter contract of which I was not told about at the time. I was only told it was a 24 months contract. I was told that the only thing they can do is charge me 60% of the remaining months which I don't have. I just wanted to cancle the contract as I am no longer able to pay and I am not using their services. I got retrenched End of June and I have my proof of letter.