When you ask the bank why they close your account, whether their answer? In my opinion there is only one reason why the bank closed the account of the person, ie since the bank go bankrupt. In my country there ever bank that went bankrupt and closed more than 1 million accounts of customers and amount to trillions. I personally still believe the bank because I am sure the bank that I chose is a bona fide bank. You can sue him in court if you do not make mistakes that lead to your account closed.