How do I remove unwanted RSS text, ads, or content below posts?

There is text displaying below all of the article excerpts in my RSS feed, how do I remove this?

Featured Images In RSS Premium provides an option to add your own content / ads above or below each post in the feed. The plugin does not place third party ads or any content automatically in your feed (besides the featured image).

If you did not add your own content / ads using our plugin, the content you are seeing is being put there by another plugin. Check to see if you are using the Yoast SEO plugin which automatically adds text to your feed to link back to your site. It’s not a bad thing especially for SEO purposes, but some people do not prefer it. You can edit or remove the text within their plugin settings:

https://www.feedotter.com/blog/remove-this-post-first-appeared-from-your-blog-posts/