Credit bureau update

I am very upset, I had a modem contract with Telkom which I paid up in full and requested for cancellation. Which it was cancelled and debit order stopped, this was early 2019. Now when I check my credit bureau statues it statee I owe telkom and the contract is still active. Whereas I paid it up in full and asked for it to be cancelled. I need this removed off my credit statues. I don't need telkom reflecting whereas I do not owe them a dim. I am so upset because the agents there are rude and don't assist in anything. I need telkom to be removed from my credit bureau statues PLEASE