Vodasure billing without consent

I upgraded my contract online last year in Dec & received the handset on 7Jan15. I was on Vodasure but decided not to continue as my home insurer could give me a better rate. Before the upgrade I had been without a phone for 3 months due to my previous handset being ******. On the 29Dec I claimed for my new phone. At some point between his upgrade & claim vodasure insurance was automatically activated on the handset by Tygervalley Vodashop unbeknown to me. In addition Vodacom had an issue with my invoicing (which I had logged) so I only picked this error up nearly 2 months later. According to a conversation I had with Felicity from Vodasure on 4Mar15 she confirmed the insurance was still active and that I have been paying the premium since Jan. I requested that she cancel the insurance immediately and give me a full refund as I had not requested the insurance to be activated. Felicity told me her manager was off sick and she would get back to me. Which she still to date has not. Now I see we are in the new month & not only had Vodasure still not gotten back to me or refunded me - I see I am still being charged the insurance premium which I was told was canceled. Please help!!