404.php — Mysterious Sub-Sub-Subfolder Error.

Hey everyone, I’m having a very strange problem at the moment with my 404 page. When I visit a fake subfolder such as:
https://www.example.com/wordpress/abc/
It works perfectly.

When I visit a fake sub-subfolder such as:
https://www.example.com/wordpress/abc/abc/
It still works perfectly!

But if I visit a fake sub-sub-subfolder, (Or anything higher than a sub-sub-sub,) Such as:
https://www.example.com/abc/abc/abc/
It only works halfway. My ‘404 Error’ image shows up, but the accompanying text, ‘Sorry, that page wasn’t found.’, doesn’t show up at all, as if the text was never there.

Everything else works perfectly, the header, the sidebar, the footer … Everything except the text.

I know this isn’t normal behaviour, so how do I go about fixing it? Here is my 404.php’s code:

<?php get_header(); ?>

<div id="container">

<div class="imagetitle">
<img src="https://www.example.com/wordpress/404error.gif" alt="404 Error" title="404 Error" /></div>
<?php if(have_posts()) : ?><?php while(have_posts()) : the_post(); ?>

<?php endwhile; ?>
<?php else : ?>
<div class="post">
<h3>Sorry, that page wasn't found.</h3>
</div>
<?php endif; ?>
</div>

<?php get_sidebar(); ?>

<?php get_footer(); ?>

</div>
</body>
</html>