Vodacom Bad service!!!!!!

I received a call from Vodacom customer service a few weeks ago offering me increased data at an additional cost of R10, obviously I accepted the "remarkable deal" that was offered to me. Days later I received migration quotations on mail showing a 'new package" with a increased cost of much higher than R10. I called the call center and requested that they cancel the migrations on the numbers effective immediately and the agents confirmed this was done. Almost two months later and to my surprise having a look at my monthly statement I'm noticing that I am still being billed for the increased amount. This means I am paying a extra R180 on each of the numbers that was "migrated", a total of R360 per month on my contract! What then is the point of calling a customer service center if they cannot assist effectively? I have now been ****** of R720! And will probably be ****** this month too if I'm looking at my statement!