First Bankcard Amtrust Bank Reward points stolen after closing account. Without being told that they would be forfeited. Internet

My account was transfered from Amtrust Bank visa to First Bankcard.  During the transfer of the account there was a balance of less than $20.00 so I waited for the next billing cycle to make sure all of the transactions had cleared.

 Upon receiving my next statement from First Bankcard there was a late charge that more than doubled the previously existing balance and a hold was placed on my account.  I contacted them and said that if the penalty wasn't removed I wanted the account closed.

They removed the penalty gave me the final balance, which I paid in full and we parted ways. After doing so I checked into redeeming my accumulated "World points" and was told that they were no longer available because I had closed the account.

This account was created/opened in 1988 and  I had over 26,000 points earned and they stole them with no verbal warning that they had the ability to do so.  By their own accounting this is worth over $400.00 cash!  

I spoke with their customer service people and they said I was S.O.L. get a lawyer.   This isn't right!!!  Am I screwed?