That makes no sense. Why would they care about what you do in regards to your account and what you post online?
And whoever quoted Elon musk issue was completely off base. He's a fucking CEO of a A PUBLIC COMPANY..so misleading tweets on direction of company deserve investigation. Was that post suppose to relate to this journal?
And how were you contacted? By email? letter?, Call? If by email, i wonder if the email from regulator isn't fake, like those emails from Nigerian prince asking your help in order for you to get money lol. Careful man, you start giving docs to people over email, next thing you know your account is locked.
One thing I learn about fraud, especially regulator fraud like the IRS fraud for example, is that those mofos won't send you email, or call. They send you official letter heads by mail or forms of ID through visitation. In fact you should verify by calling official numbers. Im sure this is similar to SEC or CME investigation...
https://www.irs.gov/newsroom/how-to-know-its-really-the-irs-calling-or-knocking-on-your-door