Fix "Error 404" page's navigation for portfolio

Either it just happen, either I didn't saw it before, but when I go into Portfolio, the limit is 12 then there is a page navigation at the bottom (up to 3 pages long). When I click on page #2 or #3, i get Error 404.

How to fix this ?

My WP

Settings - Reading - Blog pages show at most = 12 posts

My initial page's code

<div class="content-wrapper">

    <?php if ( get_query_var('paged') ) {
        $paged = get_query_var('paged');
    } else if ( get_query_var('page') ) {
        $paged = get_query_var('page');
    } else {
        $paged = 1;
    }
// THIS LINE below will call the theme's portfolio max number, which I have set to 12 also
    query_posts( array( 'post_type' => 'portfolio', 'posts_per_page' => get_option('pxp_portfolioquantity'), 'paged' => $paged ) ); ?>

        <section class="main-wrapper <?php echo get_option('pxp_gridmode'); ?> portfolio">
            <?php get_template_part( 'loop' ); ?>
        </section><!-- END mainWrapper -->

        <ul class="page-navigation" id="numbering">
            <?php get_pagination(); ?>
        </ul>

    <?php wp_reset_postdata();  // Reset ?>

        <?php if (get_option('pxp_enable_sideblogstream') == "true" ) { ?>
            <?php get_template_part( 'inc_sideblogfeed' ); ?>
        <?php } ?>

    </div><!-- END contentWrapper -->

My newer page's code (trying to fix it myself)

//same codes but THIS LINE change only to
query_posts( array( 'post_type' => 'portfolio', 'posts_per_page' =>12, 'paged' => $paged ) ); ?>