FNB *****ing from their Clients via Debit Orders

FNB is just there to ***** their clients' money. A debit order was taken off my account, and there was money short on Friday night. On Saturday morning, I rectified it. On Monday morning, they return the debit order when there is enough money in the account. This is how banks ***** money from their clients. Think of it this way, if banks do this with 5000 clients out of 100 000 clients, how much money do they make against R150 per client? Banks should give clients 24 hours to rectify their accounts if there is insufficient money for a debit order.