There are a few ways to let us know that something you see on Particle is off.
At the very bottom of a Story Detail page, there is a "Report Issue" button. Tap that button to see 4 options: "Factual errors are visible", "Harmful or sensitive content", "Image doesn't make sense", and "Something else". Use any of these options to immediately report content to our team.
Tap the 3 dots at the top right of any Story Detail, and then "Share Feedback".
In Settings (from the first tab, tap your avatar in the top right), scroll down to "Share Feedback" under "About Particle".