TSA agents were promised a $500 bonus after working unpaid for weeks. They haven’t received it.

As the longest partial government shutdown in US history continues, airport security workers have become one of the most vocal contingents of government employees who are laboring without pay.

“Every day I’m getting calls from my members about their extreme financial hardships and need for a paycheck,” resident of the national TSA employee union Hydrick Thomas said in a statement. “Some of them have already quit and many are considering quitting the federal workforce because of this shutdown.”

Transportation Security Administration, or TSA, agents are deemed “essential” employees and therefore must report to work even when they aren’t guaranteed a paycheck. However, since they haven’t been getting paid, many agents may not be able to afford child care, causing them to call out sick. Some are even trying to find cash-paying jobs while the government is shut down.

On January 11, the TSA announced that it would provide a day’s worth of pay to those who were on duty December 22, the day the shutdown was announced, plus a $500 bonus for working over the holiday season. But as the afternoon of January 16, no employees have received the bonus and some haven’t gotten their full day’s worth of pay. If this money ever arrives, it may help with the collective $438 million worth of mortgage and rent payments unpaid federal employees owe this month, but it still isn’t much.

According to BuzzFeed News, TSA Administrator David Pekoske sent an email to agency employees saying that all payments would appear in accounts no later than Tuesday, adding that this money would come from “unlapsed funds in specific TSA accounts.” This hasn’t happened.

Hartsfield-Jackson Atlanta is one of several airports that has had long security line wait times in recent days. Shekina Givens, a government workers union representative who works at the Atlanta airport, told BuzzFeed that some TSA employees have only received a fraction of their expected pay for December 22, possibly because airports had entered hours incorrectly. According to Givens, some workers who process payroll are furloughed during the shutdown, leaving the processing to staffers who don’t normally handle that responsibility.

Of the approximately 420,000 federal employees who are working without pay, 51,000 are TSA agents. And, according to WNYC, the TSA is one of the lowest-paying federal agencies, with the typical starting salary of an agent being $17,000 (other estimates say it’s closer to $25,000).

Federal workers also, by law, aren’t allowed to strike. Doing so could put their job in jeopardy, as it did in 1981 when air traffic controllers went on strike to demand better pay and working conditions. President Ronald Regan demanded that they return to work, and the ones who didn’t were fired.

With the lack of options TSA agents are provided and no finite end to the government shutdown in sight, it’s likely that tensions and anxieties at airports will only continue to rise.