That very thing happened to us only instead of holding some of our funds they wanted us to pay a deposit of 30k. And get this, the bank wanted it all in 36 hours or else they would freeze our accounts. Only difference is we had no fraud, sales were up and the bank got nervous, they figured we would suddenly take off with all their money. One nice thing is we have a local bank in town and the owner walked right over and got someone at the bank to back down. But it was scary for a couple days.