settled account in 2015 appearing on arrears

I had a contract with vodacom and was handed over to debt collectors as I didnt honour my arrangements of payments. In September 2015 I settled the account as the debt collector told me including discount I would be required to pay R3100. I payed the money and got a settlement letter. But now as I had my self checked for my credit profile the very same account appears in arrears of R788. <br> Please help<br> <br> Mzimkhulu Horatious Jako<br> [Email Removed]