Debt works given me hell, not help!!

I signed up with the company in 2015, made first installment, consultant I debt with later on left me handing when I got hold of her she explained she will try get someone else to assist as she is no longer working there. Few years down the line my credit score cannot be amended, I've been able to pay off my own debts now I needed them to assist with my credit score to be cleared, I've dealt with lady by name of Marina who has not been much help, has never even bothered to call me, now I find out one of the outstanding balances which I never knew about I still owe R8000, so what did debt works use the money for? This has ruined my day here I was thinking I'm debt free... Now I have this account.