from the article: "Musk publicly called on Whitaker to resign after the FAA fined SpaceX [a proposoed $633K] for failing to get approval for launch changes [in 2023]."
As has been commented there are many conflicts-of-interest in Musk's many positions of power since FAA regulates SpaceX, DoT/NHTSA regulates EV safety, etc. He did not divest himself of any executive positions or stockholdings before joining the admin. Not sure how this resolves itself.
UPDATE: "Air traffic controller was doing the job of two people [one for handling planes, one for helicopters] during DC plane crash due to tower being understaffed, FAA says"