I never agreed for any additional services!!!

worst service ever.. i have been with vodacom since 2010 but now i wish i never trusted their services. they have added data on one of my contract number without my concern and i had to pay for it. i called them and asked the to cancel, it was confirmed that it was done (cancelled), but then today i got an sms saying data has been added that means i have to pay for it again that is bull s***.... i am so not happy with vodacom, i just cancelled one of my contract with them i know they will still charge me for the services and they will tell me i didn't cancel, i do not trust their service anymore