Ridiculous service from FNB

I've had the worst experience ever with FNB. I mistakenly paid money into my friends overdrawn Account. When I approached FNB about it, they said it won't be a problem to reverse it. So I sent in the reversal form at the beginning of August, and each time (after 10 days of waiting), they have an issue. It's either with the form or something unnecessary. I am totally sick with this. I've resent the form last week, and I haven't received any response or reference. When I try phoning FNB, they never answer they phones. Now what must I do? Did my R400 go down the drain? FNB basically stole my money now. I need my money back asap or else I will take this up with my lawyer. I'm appealing to everyone not to bank with FNB until you find out how ridiculous they are.