Wrongfully debiting Account

I cancelled my membership at Virgin Active last month and i was assured no more money will be debited from my account... I paid my last transaction on the 25th and then i get message on the 2nd of October of a debit order from Virgin Active, more then the usual installment. I call the client care and the first guy drops the phone after confirming my details and placing me on hold for 10min. I called again and spoke to Marilyn who advised me that in order for them to refund me my money i need to send them my bank statement... After disputing with her i asked for a team leader to tell me that and she told me all the managers just \stepped into"a meeting and there isnt a manager to speak to me. .. I am very upset and dissatisfied at this incident because that money they debited is not owed to them and i have to be inconvenienced to go get a statement from my bank to prove something they can see on their system. Now i have to wait 5 days for my money!... """