Total lack of communication from vodacom

when my data contact was up for renewal i told vodacom that i will not be renewing my contract and that i would not be taking a new router. I was told then my contract would run month to month. so i could cancel a a months notice which is what i wanted. I have since filled in forms and sent it to the cancellation department. I have also sent a two further emails requesting as to what is happening. needless to say vodacom have not afforded me the common courtesy of a reply, WHY NOT