Account Frozen and FNB is avoiding me

My entire account is frozen, and no one has been assigned to investigate the matter a week later. I am a student and the thousands of rands in my account are crucial during registration time. But for all that money to to frozen over a R990 query is extremely lazy investigation on the part of FNB .

The back ground is that I traded with some one for the first time and within a hour of delivering my end, he had called the bank and had my account frozen.

1)Why is FNB holding all my money when the trade was for R990?

2) Why did FNB NOT CONTACT me to explain the transaction and allow me to forward the written agreement and Proof of Payment that he sent to me from the Online banking . .?

3)Why do I have to call 5 times to explain over and over, and visit the branch only to be told to make a phone call again?

4)Why is that a week later after all those calls and visits to the Branch I still don't have anyone attending to my account?

My funds are still frozen. This is terrible service at a time when I need the help the most. I'm disgusted by FNB's unfair and the extremely indifferent service that I am experiencing.