NO RESPONSE AFTER LOGGING QUERY!!!

I have in February 2015 logged a query with Vodacom regarding my billings and have had no response as yet. They billed me outside of my contract even though I had months before capped my account in an attempt to prevent such a situation. I will not take liability for the overbilling as I had taken precautions to ensure that I can manage my account and finances. I have requested from them a copy of the telephone conversation with the consultant and to date have received no response. Companies like Vodacom aim to victimize clients. My contracts expires in a month and I believe that this is a ploy from them to get more money out of me before i cancel my contract.