a bad one

i am holder of FNB account. i have been having unknown debit orders for four time and they have been reversing my money. But the last time they had to reserve my money they did not reverse it on time. Today i went to FNB complaining about two unknown debitors that were on my slip but the consultant stated that they cant reverse it today cause it was debited today. This is treating inconveniences for me as i am told that i can not get my money today. This is sad cause i am not a happy customer anymore. i fail to understand that why this incident has happen to me for a number of times.