Owing money for unused services

My dad joined flexi club but didn't do anything with the club as he was not able to pay it. We have never been to any trip using the membership benefits but now the stupid flexi club is demanding R75 000 from my dad just because of a contract. How does he pay for something he has never used? They keep increasing the amount every month due to their 22% interest rate but what we don't understand is how do we owe them if we have never used their services. This is crazy and need help to settle this matter. B. Mpholefole