BBM Activated without my knowledge

On the 29th September I had a look at my statement and noticed that there was an additional charge on my account. I contacted Cell C and they advised me that there is a BBM activated on my account which I activated via telephone on the 21/08/15, however I did not phone and activated this. I requested the voice recording from them as I would like to hear myself activating this. Since then they haven't bothered in phoning me back or any communication from them. My account has been debited for the past 3 months with the amount of R55 for a service I don't use or need. I explained to them that I have changed my phone from a Blackberry to a Samsung because I did not make use of BBM. I have called them on many occasions on the 29/09/15, 06/10/15 and again on the 19/10/15 the only response I get from them is that they will escalate the query and get back to me. Now not once have they called me to give feedback regarding this problem. I want my monies credited immediately and if possible the voice recording sent to me as I feel very unsafe with my account now.<br>