 Other major airlines have had cancellations, but Transportation Secretary Pete Buttigieg singled out Delta, saying the Department of Transportation received hundreds of reports of disruptions and unacceptable customer service at that airline. Buttigieg says he's made it clear to Delta that they will be held to all passenger protections, including prompt refunds to those who don't rebook. Marie Andrusiewicz, NPR News, Washington. This is NPR.