service failer

My name is lebogang id. ***. Last week on the 3rd of January, I settle both my loan via consolidation through FNB, I received paid up letter for this loan account no. *** and did not receive the paid-up letter for the other loan account no. *** whereby I called for closure request on the 4th January at the same time, yet this account has accumulated interest over and above my settlement balance and is still not closed. Am not happy with the service very disappointed with African bank