Blacklisted with an Inexisting MembershipContract

One day I was shopping @ Maponya mall in 2012 with my family, one of the gym company marketing guys approached me and explained their special of a free three months membership. I ended up giving my details but I never used their facility even a single day. Last month May 2015 I received an email from Transunion informing me that I am blacklisted by Gym Company in debts of R7911.00. I did not sign any contract binding with their terms & conditions nothing was explained further as a contract.I went to their branch immediately I was told that I had a 3 year contract since from 2012. In order for them clear my name on the credit bureau I must pay the amount in full or they must re-instate a new 3 year contract of membership & R350 even if I am not interested to gym. So to my surprise there was no procedure followed to notify me that my account is in arrears since 2012 \HOW CAN I PAY FOR SOMETHING I NEVER USED"\""THERE IS NO PROOF THAT IN THE PAST THREE YEARS I ENTERED THEIR FACILITY & USED THEIR EQUIPMENT\"" Its unfair & ******* to record administration under my name"