I was mislead when signing up

Virgin Active consultants visited our workplace KZN Sharks Board and offered us membership. I told them umhlanga branch was not convenient for me as its far and more expensive i want to sign up for DBN branch. I was then called by the call center and told them i refuse to pay for wat i didn't sign for. They promised to rectify but still nothing was done. I have since received a letter of demand from their lawyers MBD with an amount of R1940 in arrears