WRONG BILLING/NO ACCESS TO CALL CENTRE

My contract a*** expired in August, and I was switched to prepaid on 21 August. I was advised on the phone that my entire outstanding balance would be deducted at the end of August and this amount was deducted as stated.<br> <br> However at the end of September another amount was deducted. What is going on here, why am I still being debited for a closed contract! This is *****. Please assist.<br> <br> Also I can not get through to your call centre via ***, there isnt even an option for speaking to a consultant. <br> <br> What else can I do to get some assistance, PLEASE HELP!!!