Absa collecting debt twice

I had a Virgin Money Card taken over by Absa. I went through a bad financial period abut 5 years ago and went under debt counselling. About 2 years ago, my financial standing changed and I cancelled the debt counselling. I did not hear of the Virgin Money Card until I started settling my debt around August last year. I got a call from a debt collector offering me a settlement of R500 odd on a balance of R5000 odd. I accepted immediately and made payment that same evening. A few days later I got a call checking if payment was made. I confirmed yes. A week later I got a call again where we then discovered the reference was incomplete. Proof of payment was sent and I was under the impression all was sorted. Early this year I got a call from RL Daly who told me the full debt was handed over to them. I explained what happened and was told they will get back to me. Since then I am harassed by RL Daly who has informed me that Absa says that I still owe the debt and that the previous debt collector cannot be traced. This is not acceptable as I accepted a settlement and made the payment. I do not see why the call cannot be traced and debt cleared as agreed.