Incorrect information on credit bureau

I had an outstanding debt with Atlas Finance which I paid on 27/08/2025 through their collection agency, Debt Tech. I received a paid up letter 2 days later and the agent from Debt Tec assured me that they would have the debt updated with the credit bureau within 30 days. I checked my experian report a month later and the account was still in arrears, I called Debt tec again, the agent I spoke said they had submitted the information to the credit bureau, I should wait for next report for it to clear. Three reports later the account is still showing an outstanding debt which has been settled. May this matter be resolved as a matter of urgency, I need to build up my credit score but this account is holding me back.