There have only been two individuals that have agreed to pay the fines received by the Transportation Security Administration (TSA), according to a report.

The Hill reported that there had been 2,413 incidents of non-compliance since the mask mandate on planes took effect last year. Since then, the TSA has only been able to complete investigations on 1,793 incidents, among which only two people actually agreed to pay the fine.

The TSA, responding to the Hill‘s Freedom of Information Act request said, “The agency issued more than 1,690 warning notices and referred 38 matters for civil penalties. Only two individuals did not challenge their fines of $250 each.” This data comes as reports show there has been an “uproar” over the federal mask mandate, which was recently put back in place by the Centers for Disease Control and Prevention (CDC).

One explanation could be that the people who already violated it to start with are people who feel very strongly to begin with and don’t think the federal government could even mandate something like that,” said Retsef Levi, a professor at the MIT Sloan School of Management specializing in risk management and analytics.

“They do it partially as a protest, so it’s not surprising they haven’t paid the fine,” Levi added. 

According to the report:

The FAA has received more than 3,600 reports of unruly behavior by passengers, including 2,666 reports of passengers refusing to comply with federal mask mandates. It has identified potential violations in 610 cases and has initiated enforcement action in 95 cases.

“Developing a case that we believe will hold up in court takes a considerable amount of work from our safety inspectors and attorneys, and they currently are working a record number of cases,” an FAA spokesperson said.

The report noted that the fines range from $250 to $52,500. A passenger in February received a $10,500 fine after refusing to wear a mask during a flight, the FAA said.