Tap on the icon that looks like this: 
It’s at the lower right corner of the news card or the upper right corner of the article page.
A few options will pop up. You can choose to:
- "Show less about" a certain topic and you'll see fewer stories about the topic on the "For You" page;
- "Block Source" and you'll no longer see stories from them on the "For You" page;
- "Report a concern" and we'll look into it as soon as we can.