NOT UPDATING FULLY PAID ACCOUNT ON ITC

My contract *** was in arrears and amount was settled fully after my account was handed to the lawyers in 2014. Upon checking my Experian credit report recently I found thus account still appears in erraers despite having contacted them at the time and was assured the account has been settled. This also despite the letter from the lawyers that were handling my account confirming my account as settled and sent to ITC for account to be updated. A letter which I still have in my in my possession and willing to send upon request. I need this to be sorted by Vodacom.