U.S. air traffic controllers have received partial paychecks, their union said Tuesday, and they could miss their next paychecks altogether if the government shutdown lasts another two weeks.

“The job is stressful enough as it is. Now you’re adding this factor of, ‘Hey, when am I going to get this next paycheck?'” said Raymond Dahlstrom, an air traffic controller.

Dahlstrom and some of his colleagues handed out leaflets outside of LaGuardia Airport in New York on Tuesday to urge the public to ask lawmakers to end the shutdown.

The government shut down on Oct. 1, as the Senate has failed to pass a bill to fund the government.

Air traffic controllers and airport security screeners are among the thousands of government employees who are required to work despite not getting paid during the impasse.

Last week, shortages of air traffic controllers caused delays at airports, including in Nashville, Tennessee, and Burbank, California, though most facilities were sufficiently staffed.

“We’re still showing up, nobody is calling out sick … other than they’re sick,” Dahlstrom said. He said some controllers are taking second jobs like driving for ride-sharing companies to help make ends meet while they’re going without pay.

A more than monthlong shutdown starting in late 2018 ended hours after a shortage of air traffic controllers snarled air travel in the New York area.

Even outside of the shutdown, the U.S. has been dealing with a shortage of trained air traffic controllers, which has periodically disrupted flights. Airline executives have pushed for more training initiatives and more modern technology for years.

Air traffic controllers were scheduled to hand out informational leaflets at other airports in Washington D.C. and Chicago on Tuesday.

The government shutdown has also put additional focus on U.S. aviation.

Some airports including Las Vegas, the three major New York City airports and others are refusing to air a video of Homeland Security Secretary Kristi Noem that blames the shutdown on Democrats, airport officials told CNBC on Tuesday.