The federal government is suing Walmart and the fintech company Branch Messenger, accusing the companies of forcing employees to use specific accounts to access their pay and of opening the accounts on the employees’ behalf.

Walmart and a financial tech company are being sued over allegations the retail giant forced drivers to use costly, complicated deposit accounts in order to get paid and raked-in millions in the process.

The U.S. consumer finance watchdog accused Walmart and the workforce payments company Branch Messenger on Monday of forcing more than a million delivery drivers into using accounts that cost them more than $10 million in junk fees.