SIM card permanently de activated, loss of income

On Thursday, 22 October 2015, I called Cell C to cancel my contract and the number is question is ***. I spoke to a Mpho and I was rather frustrated at that time since I have been transferred from pillar to post and had to go through the same security question about 3 times before I finally ended up in the cancellations department. I explicitly told Mpho that I wanted my contract cancelled with effect 31 October as I did not want to forfeit any remaining minutes and data that was still on the card. This I emphasised to her several times. I never indicated that I wanted the sim cancelled, only the contract as I wanted to go on a pre paid option. On the 23rd October, the SIM was de activated WITHOUT ANY NOTICE. This I find completely unacceptable as this number was purely used for business purposes and thus resulting in loss of income. On the 23rd I spoke with Sibongile, and she promised that she will get a team leader to contact me as they were in meetings. On the 24th i spoke to Lebogang, the 26th Bridgette and Chilli and on the 27th to Nadine, Zandile and Nkele. All promised that a manager would call me. I'm begging a senior manager to make contact with me...