Request for a refund

I had a very bad experience with this company. I cancelled my contract with them 3 days before the deduction date and i also phoned to confirm if the contract is cancelled and the money will be deducted and they did confirm that the money will not be deducted, however on the pay day the money was deducted. I have been phoning them and following up with no feedback . They always say i must leave my details they will phone me back.