***** and bad client experience

I just called vodacom's customer care after getting an invoice of R723 instead of my normal R288, I get assisted by Tankiso who informs me that there was an upgrade done in October for the very same phone. When I inform that I never did an upgrade he tells me that I must send an email to their ***** department and call their sales team to get what happened. What kind of service is this, why do I have to do this on my side, why can't client care send an email to the ***** department. How do I then trust the company? I am told that only the sales team can freeze this amount but I have to prove that ***** was done and my account is due to be debited in two weeks time. Now my credit report is going to have arrears for ***** that was done by vodacom agents. WHERE IS THIS SO CALLED DIVCE AND WHERE WAS IT DELIVERED TO? The answer I get is "no mam we can not give you such information". I'm truly disappointed.