Displaying large images displays smaller images

Post with issue: https://esamhamzeh.com/qatar/
I haven’t regenerated other images to have different sizes yet.

The image is a featured image on an otherwise-empty post. I have created a child theme from the Pinbin theme. I want the image to be of the 1024 variety, but modifying the single.php code ends up creating a smaller image. The media settings is set up correctly (max 1024 by 1024 for large).

Pinbin Child: single.php:

<?php
/**
 * Single post template
 */

?>
<?php get_header(); ?>

	<?php if (have_posts()) : while (have_posts()) : the_post(); ?>     

   		<div id="post-<?php the_ID(); ?>" <?php post_class(); ?>>
<?php if ( has_post_thumbnail() ) { ?>
  <div class="pinbin-image"><?php the_post_thumbnail( 'large' );  ?></div>
  <div class="pinbin-category"><p><?php the_category(', ') ?></p></div>
      <div class="post-nav">
          <div class="post-prev"><?php previous_post_link('%link', '&larr;'); ?></div>
          <div class="post-next"><?php next_post_link('%link', '&rarr;'); ?></div>
      </div>
            <div class="pinbin-copy">
<?php } else { ?>
      <div class="post-nav">
          <div class="post-prev"><?php previous_post_link('%link', '&larr;'); ?></div>
          <div class="post-next"><?php next_post_link('%link', '&rarr;'); ?></div>
      </div>
            <div class="pinbin-copy">
              <div class="pinbin-category"><p><?php the_category(', ') ?></p></div>
<?php } ?>
                <h1><?php the_title(); ?></h1>
                 <p class="pinbin-meta"><?php _e( 'By', 'pinbin' ); ?> <?php the_author(); ?>, <?php the_time(get_option('date_format')); ?></p>
           		 <?php the_content('Read more'); ?>
	<div class="pagelink"><?php wp_link_pages(); ?></div>
	 <div class="posttags"><?php the_tags(); ?></div>
                <div class="clear"></div>
				<?php comments_template(); ?> 

                </div>

       </div>

		<?php endwhile; endif; ?>

<?php get_footer(); ?>

I’m terrible at CSS and WordPress in general so I appreciate any help given.