homeloan blockers

I am looking to buy a house now and the only thing blocking me is an account that was settled in July 2019. Experian SA's system is not updated thus the account is reflecting on my name and putting me in a bad light when it come to my credit score. I have been trying to get this resolved for a few weeks now but there is no answer on their phone lines. I do not want to lose out on an opportunity when it presents itself and in order to not lose out I need to get my is resolved.