Handed over to debt collectors

So - June last year I received an account on my 3G stick for over R2, 000! I have yet to receive an answer from Cell C as to WHY this month's usage was so high. After numerous queries and phone calls I was sent from the one person to the next, from the one department to the next. Cell C kept taking the money via debit order and it would cost me money every time that I had to reverse the transaction. I received a report from their IT department that gave me IP Addresses. REALLY?! What am I supposed to do with those? When trying to search the IP's I came across some unknown website. Still no answer from Cell C. Now they've handed me over to debt collectors without even informing me about that. What *** service. I am fuming. How many times must you beg a company to give you a simple explanation? How many *********** people can work at the same place? OH YES! And the money that they worked out that I owe them is for THE WHOLE DURATION of my contract... wow! PLUS - I am unable to use the 3G card as it has been suspended, yet I am expected to pay it.