Clear my name please

Please help me with fitness center they blacklisted me ..I join the gym and pay 1 month without attending and I told them due to my work late I can't come to gym they need to cancel they refuse and say I need to pay for 24months even if im not attending now I finf out that they blacklisted me. I need them to clear my name as I told them after I paid my 1st month. I don't know the email but they are based in alberton gauteng