Custom query pagination with php parameter as arg problem

Question

I have create a loop with a custom query. This query contains a php parameters that i m getting from url with GET method. The problem is that the pagination (even if it counts the posts correct at first page) is not working correct. I 'm getting 404 error at second page. This the code at my loop page:

$cat = get_queried_object();
echo '<h1 class="childcatdes">'. $cat->name . '</h1>';
echo '<p class="childcatdescr">'. $cat->description . '<br><br></p>';
do_action( 'woocommerce_before_single_product' );

$posts_per_page = 12;
$paged = ( get_query_var('paged') ) ? get_query_var('paged') : 1;


$product_args = array(
    'post_type' => 'product',
    'posts_per_page' => $posts_per_page,
    'paged' => $paged,
    'page' => $paged,
    'tax_query' => array(
         'relation' => 'AND',
        array(
          'taxonomy' => 'product_cat',
          'field'    => 'name',
          'terms'    => $cat->name,
        ),
        array(
          'taxonomy' => 'manufacturers',
          'field'    => 'slug',
          'terms'    => $_GET['filter_manufacturers'],
          'operator' => 'IN'
        )
    ),
    'orderby' => 'name',
    'order' => 'ASC',
);

$custom_query = new WP_Query( $product_args );

if($custom_query->have_posts()) {
    echo '<ul';
    while ($custom_query->have_posts() )  : $custom_query->the_post(); 
        echo '<li>';
            $link = get_the_permalink();

            echo '<a href="' . $link . '">' . get_the_title() . '</a>';

        echo '</li>';
    endwhile;


    echo '</ul>';
}
else {
    echo 'No post found.';
}
?>
<nav class="pagination">
    <?php pagination_bar( $custom_query); ?>
</nav>  

And i use this code to my functions.php file for the function pagination_bar

function pagination_bar( $custom_query) {
    $total_pages = $custom_query->max_num_pages;
    $big = 99999;
    if ($total_pages > 1){
        $current_page = max(1, get_query_var('paged'));

        echo paginate_links(array(
            'base' => preg_replace('/\?.*/', '/', get_pagenum_link(1)) . '%_%',
           'current' => $current_page,
           'format' => 'page/%#%/',
           'total' => $custom_query->max_num_pages,
           'add_args' => array(
               'filter_manufacturers' => $_GET['filter_manufacturers'],
           )
        ));
    }
}

All off these are working properly when i don't use taxonomy manufacturers at product_args.

Please advice

Answer 1

Finally i had create a taxonomy with name manufacturers and an attribute with the same name. This may caused a confict (i didn't find out more!). So i create an attribute with name brands and i use this for my custom query.