404 error

I installed this plugin and tried to change the permalink structure of a custom post type.
/%injury_category%/%postname%/
is the code i used in permalink settings. But I am getting 404 error. ‘injury_category’ is the custom taxonomy name.

function injury_post_type() {

         $labels = array(
                'name' => __('Injury','reo_theme'),
                'singular_name' => __('Injury','reo_theme'),
                'add_new' => __('Add Injury','reo_theme'),
                'add_new_item' => __('Add New Injury','reo_theme'),
                'edit_item' => __('Edit Injury','reo_theme'),
                'new_item' => __('New Injury','reo_theme'),
                'view_item' => __('Preview Injury','reo_theme'),
                'not_found' => __('No Injurys Found','reo_theme'),
                'not_found_in_trash' => __('No Injurys Found In Trash','reo_theme'),
                );

         $args = array(
               'labels' => $labels,
               'public' => true,
               'publicly_queryable' => true,
               'show_ui' => true,
               'query_var' => true,
               'rewrite' => true,
               'capability_type' => 'post',
               'hierarchical' => false,
               'menu_position' => 100,
               'supports' => array(
                             'title',
							 'editor',
							 'thumbnail'
                             )
               );

         register_post_type(__( 'injury','reo_theme'), $args);
}
//END: injury_post_type

// injury_messages
function injury_messages($messages)
{
    $messages[__( 'injury' )] =
        array(
            0 => '',
            1 => sprintf(__('Injury Updated.','reo_theme'), esc_url(get_permalink($post_ID))),
            2 => __('Custom Field Updated.','reo_theme'),
            3 => __('Custom Field Deleted.','reo_theme'),
            4 => __('Injury Updated.','reo_theme'),
            5 => isset($_GET['revision']) ? sprintf( __('Injury Restored To Revision From %s','reo_theme'), wp_post_revision_title((int)$_GET['revision'], false)) : false,
            6 => sprintf(__('Injury Published.','reo_theme'), esc_url(get_permalink($post_ID))),
            7 => __('Injury Saved.','reo_theme'),
            8 => sprintf(__('Injury Submitted.','reo_theme'), esc_url( add_query_arg('preview', 'true', get_permalink($post_ID)))),
            9 => sprintf(__('Injury Scheduled For: <strong>%1$s</strong>.','reo_theme'), date_i18n( __( 'M j, Y @ G:i' ), strtotime($post->post_date)), esc_url(get_permalink($post_ID))),
            10 => sprintf(__('Injury Draft Updated.','reo_theme'), esc_url( add_query_arg('preview', 'true', get_permalink($post_ID)))),
        );
    return $messages;

} // END: injury_messages

//Get the thumbnail
function injury_thumbnail($post_ID) {
    $injury_thumbnail_id = get_post_thumbnail_id($post_ID);
    if ($injury_thumbnail_id) {
        $injury_thumbnail_img = wp_get_attachment_image_src($injury_thumbnail_id, 'featured_preview');
        return $injury_thumbnail_img[0];
    }
}

//Modify admin columns
function injury_edit_columns($columns){
        $columns = array(
            "cb" => "<input type=\"checkbox\" />",
            "title" => __('Injury title','reo_theme'),
            "thumb" => __('Preview image','reo_theme'),
        );

        return $columns;
}

//Content for admin columns
function injury_custom_columns($column){
        global $post;
        switch ($column)
        {
            case "thumb":
                $injury_thumb = injury_thumbnail($post_ID);
                     if ($injury_thumb) {
                        echo '<img src="' . $injury_thumb . '" width="55" />';
                     }
            break;
        }
}

add_action( 'init', 'injury_post_type' );
add_action('admin_menu', 'injury_settings_menu');
add_filter( 'injury_updated_messages', 'injury_messages' );
add_filter('manage_reo_injury_posts_columns', 'injury_edit_columns');
add_action('manage_reo_injury_posts_custom_column', 'injury_custom_columns', 10, 2);
add_action( 'init', 'create_discog_taxonomies', 0 );
function create_discog_taxonomies()
{
  // Add new taxonomy, make it hierarchical (like categories)
  $labels = array(
    'name' => _x( 'Injury Categories', 'taxonomy general name' ),
    'singular_name' => _x( 'Injury Category', 'taxonomy singular name' ),
    'search_items' =>  __( 'Search Injury Categories' ),
    'popular_items' => __( 'Popular Injury Categories' ),
    'all_items' => __( 'All Injury Categories' ),
    'parent_item' => __( 'Parent Injury Categories' ),
    'parent_item_colon' => __( 'Parent Injury Category:' ),
    'edit_item' => __( 'Edit Injury Category' ),
    'update_item' => __( 'Update Injury Category' ),
    'add_new_item' => __( 'Add New Injury Category' ),
    'new_item_name' => __( 'New Injury Category Name' ),
  );
  register_taxonomy('injury_category',array('injury'), array(
    'hierarchical' => false,
    'labels' => $labels,
    'show_ui' => true,
    'query_var' => true,
    'rewrite' => array( 'slug' => 'injury-category' ),
  ));
}

This is the custom post type register code. Please help me to resolve this problem

Thanks

https://wordpress.org/plugins/wp-permastructure/