Please update my credit card information with credit bureaus.

I paid up and closed my FNB Premium Credit card account on the 27th of May 2020. I received the confirmation letter from FNB on the very same day. As of today, the 18th of July 2020, my transunion credit report shows that I'm still owing FNB despite the fact that l have sent numerous emails to their credit card department to sought out the problem. This is negatively affecting my credit rating. May you please sought out the problem.