Can an online casino refuse to pay me?

I am 20 years old from New York and the gambling age there is 18. I took 50$ to rushmoreonline.com and started to play blackjack. I got it up to 2025$. They deactivated my account now and said I need to explain the situation to the deposit/withdrawal department. In their terms and conditions it says you must be 21 or older and when I registered I miss clicked 1988 instead of 1989 which is the year i was born. They have not refused to pay me yet but what are worse and best case scenarios?