Using pagination on a CPT single page

fix_request_redirect.php

<?php
/**
 * Adding pagination for CPT section
 *
 * This is fix for using pagination on a CPT single page
 * 
 * @link 			https://wordpress.stackexchange.com/questions/233885/yet-another-custom-post-type-with-pagination-not-working-in-wordpress
 *
 * @param 	    	$request
 */
function fix_request_redirect( $request ) {
	$cpt = 'section';//Change this to the CPT slug
    if ( isset( $request->query_vars[$cpt] )
         && true === $request->is_singular
         && - 1 == $request->current_post
         && true === $request->is_paged
    ) {
        add_filter( 'redirect_canonical', '__return_false' );
    }
    return $request;
}
add_action( 'parse_query', 'fix_request_redirect' );