Disappointed in the service delivery of EXPERIAN CREDIT BUREAU

I'm so disappointed in Experian. I contacted them in Sept to hand in a dispute with regards to paid up accounts. I even went on their website to Upload paid up letters, contact them but that numbers just keep on ringing and ringing... All the other credit bureaus revert and inform you of the progress of updating your credit score BUT NOT EXPERIAN. As a consumer I always have to call, and hold on for 20min.. they do not answer emails as well...