FNB ridiculous fee

I had a debit order go off on one of my account for 17 and there happened to be no money in that particular account - this said I had R16 in my account the debit order went off FNB then put the R16 back in my account and further debited me a R110 for unpaid fees and his is totally unacceptable because of the simple fact is that it was a R1 miss. I have several accounts with FNB and From setting up an account to a simple transaction FNB really do make everyone’s life difficult.