Looping Through Custom Tax Terms and Displaying All Posts For Each

I'm using the following code to attempt to loop through each of the terms within my custom taxonomy category-film and then output the term name as a heading together with displaying all the custom posts that belong to that term

<?php $terms = get_terms( 'category-film' ); ?>

<?php foreach( $terms as $term ) : ?>

    <?php $posts = new WP_Query( 'post=film&category-film= ' . $term->slug . '&posts_per_page=-1' ); ?>

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

        <h3><?php echo $term->name; ?></h3>
        <p><?php the_title(); ?></p>

        <div class="col-md-6">
            <?php the_field('url'); ?>
        </div>  

    <?php endwhile; endif; ?>

<?php endforeach; ?>

I am finding, however, that my code outputs nothing whatsoever.

If I move <h3><?php echo $term->name; ?></h3> so that it is outside of the loop (but within the foreach loop) it outputs the names of the terms fine.

So I imagine the problem must be something to do with the loop itself?

via Chebli Mohamed