I recommend doing one's own research on this topic; the well is quite deep. Musk's greatest talent is salesmanship; that sometimes divorces from the truth.
The usual list. He clearly isn't a leftist and it angers a lot of people very much that he doesn't automatically follow the leftist commands. Doesn't make him evil or a liar. And for example making a prediction that turns out wrong also isn't a lie. It is just an opinion.
This can get you started: https://news.sky.com/story/elon-musks-lies-about-tesla-on-tw...