Blackballed for a paid up debt from 2024

Boitumelo has not sent the correctly dated paid up letter reflecting payment was made in 2024, it is now 2026 and my credit report was never updated as paid thus impacting me FOR YEARS. No explanantion, no resolution. The letter sent reflects a June 2026 payment. Experian has since picked this up but they note that the missing payments are still reflecting from 2024 negetively affecting me