Not happy

When I want to cancel my Membership in 2019 reason for they not really having better options on Airtickets as any other company they informed me only then after being a Member for many years that I owe them R6000. I did the payment but was told that I still need to be a Member until 2033. I asked them now a few times to send me detail on the arrears as I signed for a debit order when I joined. Still waiting no reply