CNN
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Federal officials say they are acting on “thousands” of complaints by Southwest Airlines customers after its days-long holiday travel meltdown – including complaints that Southwest is not making good on its pledge to issue refunds.

The Department of Transportation “has sent every complaint directly to Southwest” and is now demanding the airline “provide substantive responses” to each within 60 days.

“Since the Southwest meltdown, DOT has received thousands of consumer complaints about Southwest – including complaints about lack of ticket refunds and reimbursements for services when a traveler was stranded,” the Department of Transportation said in a statement provided first to CNN.

Southwest Airlines told CNN on Tuesday that it is processing requests for refunds within an average of about three days. The airline said it is processing “tens of thousands” of requests each day and is complying with DOT regulations.

“Southwest intends to, and is making every effort, to initiate refunds and reimbursements as we’ve stated in our Customer Service Plan – which is in alignment with the corresponding regulations,” the airline’s statement said.

The Department of Transportation has required Southwest to honor passenger refund requests “within 7 business days if the traveler paid for the ticket by card and 20 days if they paid by cash or check,” if Southwest canceled or significantly delayed a flight, “regardless of the reason.”

Southwest says it canceled more than 16,000 flights between December 21 and December 31, noting in a financial filing that the cascading logistical failures cost the airline between $725 million and $825 million in lost revenue, additional crew costs, and passenger refunds.

Southwest customers should first file their refund request with Southwest through its website, the DOT advises. If they are not getting refunds, they should then file a complaint with DOT.

This announcement comes after Transportation Secretary Pete Buttigieg told Southwest leaders on December 29 that the agency will “use the fullest extent of its investigative and enforcement powers to hold Southwest accountable if it fails to adhere to the promises made to reimburse passengers.”