Ridiculous service

I opened an account with cell c 2020/08/25 account was short with a last payment due in 2023/07/26 which wasn't debited, however the account was handed over to CSS Solotions and attorney company which they contacted me I managed to settled the account in October 2024 they then provided me with the paid up letter and account was closed... Earlier this year in January I received a call from DMC telling this very same account from cell C was handed over to them with the same amount outstanding so this really ****ed me of I send to DMC the paid up letter I received from CSS DMC then send an email to Cell C Queries Resolutions Dept and cc me in the email hence they also want clarity on this account bt with no luck and up till today I haven't received any response from cell c neither DMC I need clarity asap regarding this matter hence its messing up my credit score more Regards Zerina Contact ***