I'm trying to edit the loop in my archive.php so that when I visit a category page, it only displays the excerpts of the posts and uses the featured image as a thumbnail.

When I add "the excerpt" to the loop it displays the excerpt of the first post, but then just keeps repeating it indefinitely?

Here's the loop I'm trying to edit / modify

                /* Start the Loop */ 
                while (have_posts())  {                 
the_excerpt();
get_template_part('content', get_post_format());

                    
                }
                    
                /* Display navigation to next/previous pages when applicable */
                if (theme_get_option('theme_bottom_posts_navigation')) {
                    theme_page_navigation();
                }

Thanks for any advice or suggestions.