Billing issues and just stay on hold

Good day.<br> I have numerous numbers on one contract almost all of which are top up. My bill is about R4500pm. Vodacom does not allow upgrades if your account is in arrears - I know this because I could not upgrade previously due to R47.00. In December I upgraded two of my numbers - the implication being that at this stage my account was up to date. Due to the upgrades I this month paid R5000. Imagine my surprise when I hear this morning that I owe 6205.79 due to according to the agent \ previous arrears on my account". How is this possible as I could not upgrade if my account is in arrears. I have tried all day for someone to log a billing dispute and advise where this amount comes from because as previously indicated the majority of my active accounts are top-up. I am unsuccessful and hold on for periods up to 20 minutes with no success. I need to understand where this huge amount comes from and if I am liable to make some arrangement to pay it...but I can even find out what it is for. How do I get to speak top ANYBODY that can help me get the required information and make the required arrangements?"""