There have been numerous allegations that Elon Musk sold bitcoin to prove liquidity, and this led to the sale of 10% of Tesla's assets.
But Elon Musk denied the claim, saying that he had not sold any of his bitcoins, and that Tesla had sold some of its bitcoins in the first three months of the year & earning $ 272 million.

The news shows that Elon Musk and Tesla have chosen a large amount of bitcoin as their capital, and by accepting bitcoin for their own transactions, they are launching a bitcoin revolution.
Source:
https://cointelegraph.com/news/i-have-not-sold-any-of-my-bitcoin-elon-musk