Being Over Charged every month

I am on a smart M package which, when I took it out, was R499 a month.<br> After I upgraded, my monthly invoice comes in at over R1000 every month.<br> I was told there would be no extra charges and every time I call vodacom customer care the operators get angry with me and put me on hold or send me through to some random department.<br> I have dealt with Ntombi and Patricia and they are completely useless.<br> After I upgraded I was even paying for both the new handset as well as the previous one I upgraded from.<br> None of these details were communicated to me and now I'm paying through my teeth for the exact same package that is meant to cost R499 a month.<br>