Vodacom *****s another month from me after notice

My Smart M contract expired on 6 August 2015. On 13 July 2015 at 13h10 the afternoon I called in and spoke to Hilda, I gave notice for my contract to be switched to prepaid, she said it will only happen at the end of August on 31 August 2015 and that I should use up all my bundles before then. I asked for a reference number and she said there is no reference number, my phone number can be used as the reference. This morning my fu cken account has been credited again with the contract, I am not on prepaid. When I called your call centre now I was informed there is no cancellation loaded on the system. This is a covenient excuse and not my fu cken problem, do you understand, if my contract is not switched to prepaid before the end of today I will take legal action against you as you have already FORCED me to continue after 6 August 2015 with the contract, I am not paying for September 2015, you had better credit the contract that was loaded today and switch my number to prepaid before close of business. So sick and tired of your bull sh it service. You had 45 days notice that I wanted to switch to prepaid, contact me urgently.