A federal judge will not reopen a lawsuit against Frontier Airlines after he previously found the company was not liable for refunding the ticket purchases of plaintiffs when the COVID-19 pandemic forced flight cancelations in early 2020.

Several Frontier customers, individually and then as a consolidated case, sued the airline for breach of contract. They reportedly bought tickets ranging from $227 to $5,132 for themselves or their families, but the onset of COVID-19 prompted Frontier to cancel flights or advise customers to cancel themselves.

The lawsuit alleged that the travel credits Frontier issued were effectively worthless during the pandemic, and that the Denver-based carrier should have granted refunds for passengers who encountered a “significant change” in their flight schedule due to the cancelations.

In September, U.S. District Court Chief Judge Philip A. Brimmer dismissed the lawsuit, finding insufficient evidence to suggest Frontier’s actions broke the terms of its agreement with customers. Specifically, he determined Frontier was only obligated to provide 90-day credits to passengers who canceled their own reservations, and would issue refunds for flights the airline itself canceled only if it could not provide alternate transportation.

The plaintiffs quickly asked Brimmer to reopen the case, citing additional information that could prove their claims. For example, Jeffrey Bone, a resident of St. Louis, allegedly requested a refund after Frontier canceled his flight in May 2020. The airline claimed Bone had accepted a “schedule change through email,” but Bone maintained he did not “knowingly accept” nor did Frontier rebook him on an alternate flight.

Frontier opposed the plaintiffs’ request to amend their lawsuit to include new details, arguing the plaintiffs were merely raising facts they knew about all along, yet failed to incorporate. Brimmer agreed with the airline.

“The allegations that plaintiffs propose to add in an amended complaint all concern events that occurred in 2020,” he wrote in a March 1 order. “The facts that underlie these allegations were clearly available to plaintiffs when plaintiffs filed their most recent complaint in January 2021, and plaintiffs provide no explanation for why these allegations were not included in that complaint.”

Beyond the lawsuit, Frontier has landed in the crosshairs of Attorney General Phil Weiser, who previously indicated his office had received more complaints about Frontier between March and September 2020 than about any other company. That year, he asked the U.S. Department of Transportation to investigate the airline’s flight change policies and customer service practices.

This week, he renewed his concerns in another letter about the proposed merger of Frontier and Spirit Airlines, raising the possibility of a further decline in customer treatment should the merger go through.

“The Department of Law also continues to receive complaints concerning Frontier on a range of customer service issues, particularly regarding its failures to provide refunds or to promptly issue such refunds to consumers when required by law, including for flights cancelled or significantly changed or delayed by Frontier,” Weiser wrote.

The lawsuit would have asked a jury to award refunds to Frontier customers who fell into the same class as the plaintiffs, as well as restitution.