Harrassed 4 months after complete payment arrangement already.

I wrote a review here and got a call from Discovery saying that I do not owe them anything but I am still getting calls from their lawyers that I need to pay. I have sent the proof of payment to both discovery and that firm showing that I paid the full amount. Discovery sold or gave my information to that firm and it was also after I had made an arrangement for payment and was still within those terms. I paid off the about R4500 within 4 months. You are harrassing me now calling me end February 2025 for an amount I completely paid off in November 2024. Discovery sent my details to these people. Discovery has said I do not owe anything So discovery needs to be accountable for the fact that I am being harrassed. The proof of payments have been sent all over so check your systems and inform your lawyers. Here is there number +***