paginate_comments_links No Longer Displays

In November 2015 I successfully implemented comments pagination for a client’s website using wp_list_comments and paginate_comments_links.

Today (March 2016), the paginate_comments_links no longer displays the pagination navigation. I don’t know when this behavior started.

The code is in the single.php template used to display a post.

I haven’t been able to figure out what is wrong. Any suggestions on what I might try to do to debug this? Thanks in advance for the help.

Here’s the code snippet:

<?php
   $comments = get_comments(array(
	 'post_id' => get_the_ID(),
	 'status' => 'approve'
   ));

   wp_list_comments(array('per_page' => 100, 'reverse_top_level' => false ), $comments);
   paginate_comments_links( array('prev_text' => '? Previous', 'next_text' => 'Next ?'));
?>