Shortcode not rendering in custom theme

The shortcode to display the calendar on a page of my site is not working. I’m using a custom built theme and a custom page template for the booking page, but I’m calling the_content in it, not get_the_content, so it should be correctly filtering the shortcode.

Is there something potentially missing from my custom page template that would render the shortcode correctly?

The relevant bits of the template are basically:

<?php get_header(); ?>
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<section>	
  <?php the_content(); ?>
</section>
<?php endwhile; else: ?>
  <p><?php _e('Sorry, no posts matched your criteria.'); ?></p>
<?php endif; ?>

The page I need help with: [log in to see the link]