VODACOM AFFECTING MY CREDIT PROFILE

I once had a contract with vodacom, It was for the laptop, then missed few payments, last year around March they gave me a call where they offered me a settlement discount, they said I have to pay 961.60 then my account would be closed. I even called afterward to confirm I'd the Payment was received, they said yes they could see the payment, and the account is closed, nut now I keep on receiving calls from different attorneys to say I need the pay yhe arrears for vodacom. I tell them that I settled the account on the 6th of March 2023, then they want a paid up letter from me, which I believe it can be retrieved by vodacom not me.I then called vodacom legall, they say they can't assist with the paid up letter because the account is closed from their side, and they reffered me to customer care, and customer care say same story, They say they can see anything from their side, when I check the bureaus it shows vodacom as adverse under my name which the whole balance of R6000 PLUS. On the 29th of October I have sent them an email, explaining my situation,I just got an acknowledgement email, buy there is no response to my matter.