Amid surging travel demand, American Airlines has canceled hundreds of flights and the carrier is projecting 50 to 80 flight cancellations per day. Staffing shortages and maintenance were cited for the cancellations.

American Airlines canceled 123 flights on Saturday and had 180 cancellations on Sunday. Ninety-eight flights were pre-emptively canceled for Monday.

As the country has opened up, there has been a surge for travel-industry companies and many like American Airlines have struggled to adjust after the shutdowns during the peak of the pandemic.

“The first few weeks of June have brought unprecedented weather to our largest hubs, heavily impacting our operation and causing delays, canceled flights and disruptions to crewmember schedules and our customers’ plans,” Shannan Gilson, a spokesperson for American Airlines, told CNN.

“That, combined with the labor shortages some of our vendors are contending with and the incredibly quick ramp-up of customer demand has led us to build in additional resilience and certainty to our operation by adjusting a fraction of our scheduled flying through mid-July.”

American Airlines had canceled about 6% of its flights and plans to cancel 1% of its flights every day.

The company has said that some customers can be moved onto earlier or later flights, or connect over a different hub, while others will receive refunds, the Wall Street Journal reported.

American Airlines, the industry leader in total number of passengers, has the most scheduled flights of any airline.