Ratings not Working

Voting on ratings worked one day, and didn’t the next. No other changes were made to the site within that time.

Here’s the code I am using:

<?php
  $args = array(
    'post_type' => 'reviewer',
    'posts_per_page' => -1,
    'meta_key' => 'ratings_users',
    'orderby' => 'meta_value_num',
    'order' => 'DESC'
  );
  $loop = new WP_Query( $args );
  while ( $loop->have_posts() ) : $loop->the_post();
?>
<tr>
  <td>
    <?php echo do_shortcode('[ratings]'); ?>
  </td>
</tr>

I then go on to close the table etc.

The plugin is generating as a static image rather than a link to click on.

https://www.ads-software.com/plugins/wp-postratings/