Activated contract without my concern

I need assistance please the Gym company activated a contract without my concern they with a bank account number that's not mine with my details.

I was approached by a consultant at bara taxi rank and the agreement was that I want to see their premises he said I need to fill in their form and assured me it was not a contract.

only to find out now that I am blacklisted owing them an amount of R1493.

when I ask to cancel they say I must pay R1500 which is a lot of money for something I did not agree to this is a major problem.

I need this resolved please, your consultants are not honest!!