Pathetic SERVICE!!!!!!

I was billed an amount of R2540 on my account after having upgraded my contract to a smart S. I asked for a closed contract fixed amount of R578. I have called numerous times to the call center trying to resolve this. All i keep being told is someone will call me back. IT'S BEEN 3 WEEKS AND STILL NO ANSWER. I am told very quickly if I don't pay the amount my phone will be switched OFF. BUT NO ONE CAN CALL ME BACK. I have been with Vodacom for more than 10 years and this is the worst service I have ever experienced from a company.<br> <br> ALL I WANT IS SOMEONE TO RESOLVE THIS AND HAVE THE DECENCY TO CALL ME!!!