Chase Bank credit card holders have unfairly been hit with high interest rates and fees on cryptocurrency purchases out of nowhere beginning in January, a class action suit filed in Manhattan federal court alleges.

Previously, purchases by Chase cardholders on the cryptocurrency exchange websites were treated as simple purchases. But then, according to the suit filed on behalf of Idaho resident Brady Tucker, one day in January “Chase decided to do something very different.” Tucker’s Jan. 27 purchase of $588 worth of cryptocurrency from the site was treated as a cash advance and hit immediately with a 26 percent interest rate, according to the complaint.