Unjust Closure of Account

My account was closed by FNB. I have bitcoins i own and i sold the bitcoins and i got the money in my account. The next thing i saw was my account was locked. I called the ***** department and was referred to A lady Alene palmer with email *** and she told me to send her proof of funds and what i did with my funds and a police affidavit and i went to the Police station to get all that and submitted to her. I got an email few hours later my account has been terminated. I have been using the account for over 3 years and never once have i had any issue. I was even a Private client with FNB and i feel FNB should hear my own side of the story. If it's a crime to trade my bitcoins i won't sell to the account again but just terminating my account is unfair and unjust.