not found message for wordpress custom taxonomy -

i created custom taxonomy named cancers , template file taxonomy named taxonomy-cancers.php when call url:

http://localhost/cancers http://localhost/?tax=cancers

wordpress shows page not found , doesn't use taxonomy template. code defining custom taxonomy:

add_action( 'init', 'create_cancers_taxonomy', 0 ); function create_cancers_taxonomy() { // add new taxonomy, make hierarchical (like categories) $labels = array( 'name'                   => _x( 'سرطان‌ها', 'taxonomy general name' ), 'singular_name'  => _x( 'سرطان', 'taxonomy singular name' ), 'search_items'   => __( 'جستجو در میان سرطان‌ها' ), 'all_items'              => __( 'تمامی سرطان‌ها' ), 'parent_item'    => __( 'دسته اصلی' ), 'parent_item_colon' => __( 'دسته اصلی:' ), 'edit_item'              => __( 'ویرایش سرطان' ), 'update_item'    => __( 'بروزرسانی سرطان' ), 'add_new_item'   => __( 'افزودن سرطان' ), 'new_item_name'  => __( 'عنوان سرطان' ), 'menu_name'              => __( 'سرطان‌ها' ), ); $args = array( 'hierarchical'   => true, 'labels'                 => $labels, 'show_ui'                => true, 'show_admin_column' => true, 'query_var'              => true, ); register_taxonomy( 'cancers', array('cancer', 'post'), $args ); } 

i think forgot add rewrite parameter in arguments,

use arguments:--

$args = array(     'hierarchical'      => true,     'labels'            => $labels,     'show_ui'           => true,     'show_admin_column' => true,     'query_var'         => true,     'rewrite'           => array( 'slug' => 'cancers' ), ); 

note:- after changing this, please update permalinks settings --> permalinks once...