Regulators at the US Securities and Exchange Commission (SEC) have sent Tesla two separate warnings around CEO Elon Musk's use of social media, the Wall Street Journal has reported.
Tesla and the US government agency settled in 2018 after alleging Musk's tweet about a potential buy-out of the company was fraudulent.
As part of that agreement, he agreed to have public statements about Tesla overseen by the company's lawyers.
However, the Wall Street Journal story says the SEC wrote to Tesla twice - once in 2019 and once in 2020 - indicating Musk's tweets hadn't been approved. The communications hadn't previously been reported on.
Tesla had failed "to enforce these procedures and controls despite repeated violations by Mr Musk" wrote Steven Buchholz, a senior SEC official.
"Tesla has abdicated the duties required of it by the court's order."
Musk tweeted about Tesla's solar roof production volumes and the company's stock price.
As well as requiring his tweets to be pre-approved, Musk and Tesla had to pay US$20 million in fines.
The billionaire's social media musings have been drawing attention again recently, with his public pronouncements sending the value of cryptocurrencies up and down.
After asking his followers whether they wanted Tesla to accept dogecoin as a payment option, the price of the meme-based cryptocurrency spiked by 20 percent.
Bitcoin slumped after he announced last month the company would no longer accept it for car purchases, citing environmental concerns.
