The president of the United States has been repeatedly blaming the biggest legislative failure of his administration on a senator in a made-up hospital, and no one in the White House is quite sure why.

Starting Wednesday, President Donald Trump has insisted seven times, in public comments to reporters and via his Twitter account, that Republicans failed to deliver on his campaign promise to tank Obamacare because “you can’t do it when somebody is in the hospital.”

That somebody—“one senator” who is a “great” guy, Trump says—is Sen. Thad Cochran (R-MS), who is not in the hospital. Cochran and his office were forced to clarify this repeatedly. The senator himself tweeted: “I’m not hospitalized, but am recuperating at home in Mississippi and look forward to returning to work soon.”

And yet, Trump continued to make this excuse, most recently on a Thursday morning broadcast of his latest Fox & Friends interview.

“Oh, Pete, the health care bill didn’t go down,” Trump told Pete Hegseth, the Fox News interviewer. “We have the votes, but reconciliation is a disaster... We don’t have enough time because we have one senator who’s a ‘yes’ vote―a great person―but he’s in the hospital.”

White House officials could not quite rationalize why President Trump keeps promoting the bizarre claim. One senior Trump aide told The Daily Beast that the president was “just, you know, doing his thing,” in riffing on a topic and reiterating a false claim to which he feels attached. Another said the media was engaged in hair-splitting to ding the president. But when The Daily Beast emphasized that the failure of the repeal effort had nothing to do with a sick lawmaker, the official did not respond.

Another White House official, however, did, only to sarcastically reply: “tax reform going great.”

Officials spoke on the condition of anonymity in order to speak freely about a fake hospital.

Trump’s lie about Cochran isn’t the first time that he has left his aides completely baffled by their boss’ wild assertions or conspiracy-theorizing. And, as in the past, this one left Trump’s public defenders in tough spots.

White House press secretary Sarah Huckabee Sanders did not address The Daily Beast’s repeated emails on the subject Thursday morning. But during the afternoon’s White House press briefing, she insisted that it was the administration’s “understanding” that “the senator was physically unable to be here this week.” She also insisted that Trump has been saying “in the hospital” as shorthand for “physically unable to be here” in Washington, D.C.

But Sanders also repeated the incorrect talking point that the White House has “the votes on the substance” of repealing and replacing the Affordable Care Act—just not the process or the bill itself.

It was not entirely clear what was meant by the latter point.