Debit orders returned while funds were available

Last night I went through my statement to check my debits, I realised that there are 2 debits that had not gone off as yet and funds wont be enough. I transferred money from my other linked FNB account to ensure that there is enough. The 2 debits went off at around 2am today, guess what, they have been failed but money is there. I am really upset with FNB as it means they are going to charge me their exhaubitant fees.....and the effect that has on my credit rating. I am really upset with them.....times are tough to be ****** like this