Account problems

I have paid up the account with Autopage, to my surprise I got a phone that I still owe them R6723.43. when I want to know for what its a story of contracts and I have been paying up to end of Oct last year, and I have ask them a letter that I have paid up my account, which I did not get, as they send me to all corners. Now they say I owe them R6723.43 and they have handed me over to VVm and I have to pay that amount of money. before all this I was talking to Zandile Janda at this no. *** but today she is not helping sending e mails no respond