Fixing Custom Post Type Archive Pagination WordPress 404

Fixing_Custom_Post_Type_Archive_Pagination_WordPress_404.php

<?php
function custom_posts_per_page($query) {
    if ( !is_admin() && $query->is_archive() && is_post_type_archive('packages') ) {
        $def_ppp = 4;
        $ppp = isset($_COOKIE['ppp']) && (int) $_COOKIE['ppp'] > $def_ppp ? intval($_COOKIE['ppp']) : $def_ppp;
        set_query_var('posts_per_page', $ppp);
        set_query_var('city', 0);
        set_query_var('class', 0);
    }
}
add_action('pre_get_posts', 'custom_posts_per_page');