Wp-Discuz not showing

Hi, WP Discuz is not replacing the default comment system. I contacted my theme developer team regarding this problem and they said
“Please check in /comments.php the code where the comments section is printed out: comment_form( $args );
Try to replace it with your own code, or maybe a shortcode.”

I’ve found comment_form( $args ); but what do I replace it with, to make it work?

https://wordpress.org/plugins/wpdiscuz/