No comunication with outstanding amounts

FNB has been very unprofessional with regards to sorting out my accounts. In January I contacted all my creditors including Fnb which I called from their branch to get all credit settlement amounts, which in turn I only was told about my credit card which has been paid in full and I have received my paid up letter. Today the 12/02/2016 I find out that there is a cheque account that is outstanding with an account number that isn't correct and has a amount that isn't due. When ask why I wasn't contacted with regards to the amount they told me it's because the account is still open which is a bad excuse due to the account hasn't been used since 2013. I have not heard from FNB with regards to this account and now due to interest I owe more than what it was originally. When I asked for a settlement amount on the 2 accounts which are still active and ask to be given discount on the amounts I was told that they don't give which isn't correct due to there is interest added. FNB pass the buck when I ask why this was never escalated so that it could have been resolved a while ago which they did with the credit card I had. This is poor business from FNB.