WP PageNAVI正在获取404页

Question

我进入第二页时在wordpress中使用wp_pagenavi插件，但它得到404错误页面。

插件URL： https://wordpress.org/plugins/wp-pagenavi/

页面网址： http://roymans.devserver1.nl/productcategorieen/blindklinknagels/spreid-blindklinknagels/

$paged = get_query_var('paged') ? get_query_var('paged') : 1;

$args = array( 'post_type' => 'product', 'post_status' => 'publish', 'posts_per_page' => 2, 'paged' => $paged );

if($parent_term->slug) {

$args['tax_query'][] = array('taxonomy' => 'product_cat','field' => 'slug','terms'=>$parent_term->slug);
        }

$loop = new WP_Query( $args );

if($loop->have_posts()) {
?>
        <!-- start kennis_Txt -->
        <section class="kennis_Txt largeproduct in_de_sec ">
          <div class="center_container clearfix">
            <div class="blok_3 clearfix category-product-block">
              <h3 class="align-center"><?php echo $parent_term->name; ?></h3>
              <div class="category-product-wrap">
                <?php while ( $loop->have_posts() ) : $loop->the_post(); ?>
                <div class="keni_blok">
                  <div class="img_blk p-10"> <a href="<?php the_permalink(); ?>">
                     <?php
                     if ( has_post_thumbnail() ) {
                            the_post_thumbnail('project-thumb');
                        }
                        else {
                            echo '<img src="' . get_bloginfo( 'stylesheet_directory' ) 
                                . '/images/no-product.png" />';
                        }
                     ?>
                    <?php  ?>
                    </a> </div>
                  <div class="txt_blk">
                    <div class="pad_t">
                      <h2>
                        <?php the_title(); ?>
                      </h2>
                      <p><?php echo substr(strip_tags(get_the_excerpt()), 0, 300); ?>...</p> <a href="<?php the_permalink(); ?>" class="ovr_btn">Bekijk product</a> </div>
                  </div>
                </div>
                <?php endwhile; ?>

                <div class="clearfix"></div>
                <div class="navigation">
                     <?php wp_pagenavi( array( 'query' => $loop ) ); ?>
                </div>
              </div>
            </div>
          </div>
        </section>
 <?php } ?>