The Consumer Financial Protection Bureau (CFPB) has filed a lawsuit against Capital One, alleging that the bank misled customers about its savings accounts, causing over $2 billion in lost interest. Capital One allegedly froze interest rates on its '360 Savings' accounts at 0.30%, while launching a higher-yield '360 Performance Savings' account with rates up to 4.35%. The CFPB claims Capital One failed to notify existing clients about the higher-rate product and restricted employees from providing information. The bank denies the allegations, asserting its products are competitive and accessible to all customers.