Trying to cancel Cell C contract

I am trying to cancel my contract with them for the past 6 months and every time I finally get to a consultant I have to do all the security question and then wait to be transferred to another consultant who tells me that I owe R1602,93. Then I pay that and when I am trying to cancel after that they just tell me again I owe R1602,93. I've paid it twice and still struggling. I have talked to about 20 different consultants by now And every time it is the same. I really don't know what to do next. I have sent through my proof of payments but still nobody answered that e-mails.