No. Markets on Ethos Trade can't be closed or removed, by you or by the person who created them. Anyone can create a market for any X account, the same way anyone can write a review.
What you can do
Build your profile. Reviews, vouches and verification show people more than a market price does.
Trade it yourself. If you think the market has you wrong, you can buy trust like anyone else.
The market only affects your credibility score once several people are trading it. See How Ethos Trade affects your credibility score.