Deductions for expired and cancelled contract

Virgin Mobile continue to deduct money from my bank account even though my cell phone contract expired in January 2016. I cancelled the expired contract with Virgin Mobile within the required time period (Spoke to Mpho). The reference number for this is VRMN***0. I have physically been into my bank on several occasions to reverse their ******* deductions and to block Virgin Mobile from taking further amounts out of my bank account. However, Virgin Mobile persist in taking money out of my bank account by changing their transaction reference numbers since their original reference number was blocked by the bank. <br> I have previously experience misconduct by Virgin Mobile. For a period of over a year, Virgin Mobile deducted double monthly payments from my account for a single contract, i.e. they deducted amounts for two contracts on the same cell number and it took me over a year and private access to their CEO to get them to stop and to refund me the total accumulated amount of unauthorized payment.<br> PLEASE HELP.