GYM Company de***** their clients

I signed a gym contract with the GYM Company at Winchester Hills in 2008, i had the contract for one year and decided i didn't want it anymore, i sold a contract to another lady and the contract was transferred from my name to another person, i stopped paying in 2009, because i was no longer liable for the gym membership, fast forward to 2015, i got a letter from Gym Company that i owe them money, they immediately put my name on ITC for owing money, i told them that i don't owe them a cent because i transferred the membership, they tell me they have no record of this, because the consultant i signed up with has left and there is no record of the transfer. How is it my fault that these people don't have paper trail and that's when consultants leave they take their papers with them, why are these things not in the computer in 2015. So not i am listed on the credit Bureau and the stupid Gym company doesn't care because they got paid and i am getting *****ed. Don't signup with GYM Company they will de***** you.