Airlines are picking a new fight against the Biden administration’s automatic refund rule — a policy recently enacted in a must-pass spending bill this spring that guarantees customers are returned their money for delayed or canceled flights.

The move comes just as the airlines attempt to block a different consumer protection from the Biden administration. On Monday, the U.S. Court of Appeals for the Fifth Circuit, a notoriously industry-friendly court, granted airlines a major win by stalling a Department of Transportation rule taking on airline junk fees, extra fees for bags or seating.

Now, the airlines want to stop consumers from getting potentially billions of dollars back in refunds for unused flights, too.