Deduct more money than what was available in acc

I took out a temporary loan to be repaid when my salary is paid. I got outstanding money into my account which was less than the temporary loan amount which would carry me through to payday. Now this morning I see that the temporary loan was deducted and now my account is in a negative. I also received a sms that I need to make a payment to rectify this.<br> <br> Just tell me how this is my fault? The deposited money was less than the loan amount. Surely FNB must deduct when the outstanding amount can be paid from the deposited money and not when it's less?<br> <br> I need that money back. Payday is only Saturday and I'm now in a minus.<br> <br> Get your act together FNB.<br>