Incorrect billing and terrible attitude

Incoorect amount of an extra R500 added to my account, phone and explain to Vodacom to get put through to 5 different departments only to be told to email to ***** disputes. Then I get harassed over the phone as I didn't put it through to accounts. I have been waiting over 2 weeks to get this resolved. How am I supposed to know details, I didn't even know what the R500 is for, except an "upgrade" which I didn't do. Mess up from Vodacom, really disappointed.