Account queries

This company claimed that they did not debit my gym fee but according to my bank the amount was reflecting on my statement and i complained they wanted me to provide them with the statement, i did that but they still did not admit that the money was debited. I was charged arrears for four months until i accepted to pay whatever they said i was behind with, Simply because these guys when you don't pay they list you to credit bureau, This is abusing clients and i cant wait to finish my contract with them