I cannot get product variations to show up

Hi, I'm building a custom theme using the functions from the marketpress plugin. I have a page using mp_product.php. Everything seems to be working fine, except when a product has a variation. It doesn't show the dropdown menu. I've tried mp_product_meta() and using the different parameters.

Here's what I have:

<aside class="product-info">
		<div class="product-info-inner">
			<?php
				if(get_field('company'))	{
					echo '<span class="made-by">' . get_field('company') . '</span>';
				}
			?>

			<h3 class="pv-product-name">
				<?php
					mp_product_title($product_id, true, false, false, '', '', '');

					mp_product_price(true, $post_id, false);
				?>
			</h3>

			<div class="product-description">
				<?php the_content(); ?>
			</div>

			<div class="product-actions">
				<?php mp_product_meta(true, 'single', false, $product_id, false, 'mp_product_meta'); ?>
			</div>
		</div>
	</aside>