Charged without using their gyms

Last year late 2015 around September, i was at Mark Park shopping complex and Sipho from Slater approached me about their promotion. I singed up and i paid R150 upfront, then they gave me promotional items: A/C, BAG, TOWEL, W/BOTTLE. AFTER JOINING THE GYM I DIDN'T EVEN ATTEND THE SINCE UNTILL NOW 13 MARCH 2016. Then on the 23 January 2015 i received the email that reads as follows \From: Lawrence Moloi<br> PHILISO<br> OUR CALL CENTRE NUMBER: ***<br> <br> Please call us on *** regarding the outstanding amount of R1466.23 which is still due to Slater Fitness & Health.<br> Ref SLA02241<br> <br> Kind regards<br> Hybrid Collections (Pty) Ltd <br> <br> ***<br> ***<br> PostNet Suite # 81, Private Bag X7, Aston Manor, 1630\"<br> Then i rep**** as follows immediately after getting the email \"Good day<br> <br> Mr Moloi<br> <br> I tried calling the number and it hust rings.<br> <br> I do not believe that i owe slater because i haven't been to slater gym for more than three years. Last year i joined slater and i have never set foot in slater, they can check their records. I do not know the R1466.26 is for.<br> <br> Kind Regards<br> Mkhuseli Philiso\" then on 22 February i received a call from Hybrid collectors, demanding a payment from me of R1684. "