The Consumer Financial Protection Bureau (CFPB) is suing Capital One, alleging the bank illegally misled customers by not notifying them of account options that paid higher interest rates.The federal government's consumer watchdog claims Capital One's practices meant millions of customers missed out on a collective $2 billion they could have made in interest payments.

Despite its relatively low interest rate, the CFPB alleged, the 360 Savings account was advertised as a high-interest savings account.