Call Centre Said my contract was cancelled but still debiting

I had currently hurt my knee sometime in March 2017 quite badly at work and decided that I should rather cancel a contract with VIRGIN ACTIVE PAVILION that I had opened round about mid Jan to mid Feb 2017 as I would be paying for a service that I'm not using. Instead I was told to pay the full 12 month contract and they would give me 40% discount which I was not able to afford, a month or so later I received a call from their call centre saying that my contract cancellation had been approved and that a last payment will taken round about the end of May 2017 (stand to be corrected). Now 22/09/2017 and VIRGIN ACTIVE PAVILION are still debiting my account for a Service that I have not used and will not use because of the injury I had sustained early this year. I feel that I am been taken for a ride and I would like to be reimbursed.