In his letter (PDF), Pallone stressed that bad actors can use information from carriers to track anyone they want, and the meeting can't wait until the president reopens the government. However, Pai doesn't seem to think that the issue is serious enough for an emergency briefing. Pallone said in a statement that in "a phone conversation today, [Pai's] staff asserted that these egregious actions are not a threat to the safety of human life or property that the FCC will address during the Trump shutdown."
Here's the thing, though: Pai has no legal reason to turn down Pallone's invitation, because he's still working and isn't affected by the government shutdown at all. "There's nothing in the law that should stop the Chairman personally from meeting about this serious threat that could allow criminals to track the location of police officers on patrol, victims of domestic abuse, or foreign adversaries to track military personnel on American soil," the lawmaker explained.
Pallone wanted to know what steps the FCC is taking to address the issue, seeing as Ron Wyden also exposed how carriers sell location tracking to data aggregators way back in mid-2018. While the US mobile carriers involved in the scandal already swore that they'll sever ties with aggregators, the lawmaker argued that we can't trust their word anymore -- they've been promising that for quite a while, after all.