Comment counter beside name name does not work for every site

I have a problem when showing the comment counter on my website.

It's working on my site but when I move my site to a new subdomain using Duplicator plugin, it does not show anymore. I have checked the functions.php file and every line of code still there.

The working screenshot:

It does not display comment counter any more:

The code:

/**
 * Add comment next username Wpdiscuz
 */
add_filter('wpdiscuz_comment_author', 'my_commentCount', 10, 2);
function my_commentCount($author_name, $comment) {
    global $wpdb;
    $no_comment = "No comments";
    $one_comment = "1 comment";
    $more_comments = "% comments";
     $count = $wpdb->get_var('SELECT COUNT(comment_ID) FROM ' . $wpdb->comments. ' WHERE comment_author_email = "' . addslashes($comment->comment_author_email) . '"');
    $comment_text = my_comment_number_text($no_comment, $one_comment, $more_comments, $count);
        return $author_name .' <span class="wpdiscuz-comment-count">'.$comment_text.'</span>';
}
function my_comment_number_text( $zero = false, $one = false, $more = false, $number = 0 ) {
    if ( $number > 1 ) { $output = str_replace( '%', number_format_i18n( $number ), $more); } elseif ( $number == 0 ) { $output = $zero; } else { $output = $one; } return $output;
}

Please advice.

Thanks