Infinite scroll spinning, but not loading posts

Hi,

I’m trying to get the infinite scroll feature to work on my custom theme (created from scratch). Everything appears to be working, apart from the fact that it’s not actually loading additional posts.

When the type is set to “scroll”, the spinning thingy appears, but no posts are loaded. When the type is set to “click”, the button appears, but clicking it only shows the spinning icon for a second, but nothing loads.

This is in my functions.php:

add_theme_support( 'infinite-scroll', array(
	'container'  => 'contentposts',
	'footer' => false,
	'type' => 'click',
) );

And this is the loop code I’m using on home.php:

<div id="contentposts">
		<?php if ( have_posts() ) : ?>
		<?php while ( have_posts() ) : the_post(); ?>
		<?php get_template_part( 'content', get_post_format() ); ?>

			<div class="post">
			<?php if (has_post_thumbnail()) : ?>
				<div class="entry-image">
					<a href="<?php the_permalink(); ?>" target="_parent" title="<?php the_title(); ?>"><?php the_post_thumbnail(); ?></a>
				</div>
			<?php else : ?>
			<?php endif; ?>
				<div class="entry-header">
					<div class="post-edit">
						<a href="<?php echo get_edit_post_link( $id, $context ); ?>" target="_parent" title="Edit">Edit post</a>
					</div>
					<div class="entry-data">
						<span><?php the_date(get_option('date_format')); ?></span>
					</div>
					<h1 class="entry-title"><a href="<?php the_permalink(); ?>" target="_parent" title="<?php the_title(); ?>"><?php the_title(); ?></a></h1>
				</div>
				<div class="entry-content">
					<?php the_excerpt(); ?>
					<a class="button" href="<?php the_permalink(); ?>" target="_parent" title="<?php the_title(); ?>">Read more</a>
				</div>
			</div>

		<?php endwhile; ?>
			<?php else : ?>
				<div class="post">
					<div class="entry-post">
						<h1>No posts were found.</h1>
					</div>
				</div>
        <?php endif; ?>
</div>

Am I missing something here?

I can’t link to a live website, because I’m currently developing on a MAMP server.

PS: MAMP isn’t the problem. The infinite scroll feature does work with the Twenty Fifteen theme, so it’s something that’s wrong with my custom theme.

Thanks in advance.

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