False advertising!!! Targeting & blacklisting students

Early Jan 2017 on my way home from school, i was stopped on Durban Field street by one of the gym salesman (Musa) advertising a free voucher for a month at bodylab gym. He convinced me that it would only take a minute and i should hear him out. And so i did. He sat me down, and briefly explained the free voucher that would last for a month and how i can get to enjoy the gym's facilities FREE of charge. Knowing that i was a student fresh out of high school, he convinced me to sign a contract he made me believe it was the voucher that he was advertising and telling me about. He also assured me that i don't need to read it's content because, he had already covered it. Not knowing any better I signed what i thought was a ONE MONTH FREE VOUCHER and put my details down where he told me to. He told me that after a month, I then can decide from there wether i continue visiting the gym, and sign a full gym membership contract. He gave me the copy of the voucher and told me not to lose it, because that would be my ticket into the gym. Got home told mom about this voucher and how i was excited about it. But as a university student, i never got the time to visit the gym and use the voucher. A month passed and i was under the impression that the voucher had expired, so i deposed of the voucher. I started receiving messages and calls from debt collectors, forming me that I had a gym membership and was owning an amount that had accumulated to R6000+, and that legal actions would be taken if i ignored them. Months had passed and the threats continued this really is affecting my studies. I am appalled at the manner in which bodylab conducted its marketing. Today i am told i have a contract with the gym, and if i fail to pay i will be blacklisted. Musa *********ly and deliberately misled me to sign a voucher that he knew it was a contract. In my research there are more students who are victims for the same **** and are already blacklisted.vsurly there are corrective measures for this action. When i went to report this at the bodylab gym on Durban Smith Street, all they was show me a contract that i had apparently signed but had no knowledge of.