DENVER (KDVR) — Thousands of flights have been canceled around the country as the arctic storm that hit Colorado moved east across the U.S.

The majority of canceled and delayed flights at Denver International Airport on Thursday were through Southwest Airlines, according to FlightAware.

Some travelers who flew Frontier Airlines said their flights were canceled without their knowledge, and it’s been difficult figuring out another plan ahead of the weekend.

“We’ve been here since 5 a.m.,” said Thuan Nguyen, who planned to take his family to Jamaica for the holidays. He lives in Denver and tried flying out of DIA on Frontier Airlines.

Carlos Amaya flew through Denver from Washington D.C. on his way to San Francisco, also on Frontier Airlines.

“By this time, I should have been in San Francisco,” Amaya said, “you know, in my hotel room, relaxing a little bit.”

Travelers frustrated by airport chaos

Both men said they’ve been receiving text messages throughout the day about their flights.

“Then we had to move to different gates, multiple times,” Nguyen said.

Delays or cancellations were expected with the cold front coming through the metro area, but Nguyen saw his gate’s destination change from Jamaica to Mexico.

“That’s when I realized that they canceled the flight,” Ngyuen said. “They did send an email but I wasn’t checking email.”

“Like everyone else, it’s just been a nightmare trying to get through to them,” Amaya said.

Nguyen provided a video to FOX31 showing long lines and crowds at the Frontier customer service counter.

Amaya said he was given the option to fly out another day.

“To fly out three days from now, you know,” Amaya said, “four days from now. I mean four days from now, I mean the holidays are over.”

FOX31 requested a statement from Frontier Airlines about these customers’ experience, multiple times, but did not receive a comment.