Elon Musk is once again in the crosshairs of the Securities and Exchange Commision (SEC). The regulator, which has been investigating Musk’s Twitter takeover, is now suing the owner of X after he failed to appear for previously-scheduled testimony, The Wall Street Journal reports.

The SEC’s investigation dates back to 2022, when it opened a probe into Musk’s delayed disclosure of his stake in Twitter, which was at the time a publicly-traded company. Musk was 10 days late in filing paperwork, required under US securities law, disclosing his investment in Twitter. The delay may have earned him as much as $156 million, and also made him the target of a class-action lawsuit from former Twitter shareholders.

Musk had been scheduled to testify in the SEC investigation into the matter last month, The Wall Street Journal reports. But Musk failed to appear at a scheduled meeting in San Francisco, and later gave a “blanket refusal to appear for testimony” when the SEC tried to reschedule. The regulator is now asking a San Francisco federal court to force Musk to comply with its subpoena.

It’s hardly the first time Musk has found himself on the wrong side of the SEC, which he has repeatedly ridiculed over the years. The Tesla CEO was charged with securities fraud over a now-infamous 2018 tweet claiming he had “funding secured” to take the electric car maker private. Musk eventually settled with the SEC, paying a $20 million fine and giving up his position as chairman of Tesla’s board. Musk is, however, still fighting a provision of that SEC settlement requiring a so-called “Twitter-sitter” to sign-off on some of Musk’s Tesla-related tweets.

X didn’t respond to a request for comment.