Metabox not saving values

This is my working code

// Add meta box
function frontpage_meta_boxes( $post ){
    global $post;

    if(!empty($post))
    $page_template = get_post_meta( $post->ID, '_wp_page_template', true );
    {
        $pageTemplate = get_post_meta($post->ID, '_wp_page_template', true);

        if($pageTemplate == 'page-home.php' )
        {
            add_meta_box( 'frontpage_meta_box', __( 'Features' ), 'frontpage_meta_box', 'page', 'advanced', 'high' );
        }
    }
}
add_action( 'add_meta_boxes_page', 'frontpage_meta_boxes' );

// builds our meta box
function frontpage_meta_box( $post ){
    // make sure the form request comes from WordPress
    wp_nonce_field( basename( __FILE__ ), 'frontpage_meta_box_nonce' );
    // retrieve the _manuf_url current value
    $manufacturer_url = get_post_meta( $post->ID, '_manuf_url', true );

    ?>
        <h3><?php _e( 'Manufacturer URL' ); ?></h3>
            <p>
                <input type="text" name="manufacturer-url" value="<?php echo $manufacturer_url; ?>" /> 
            </p>

    <?php
}

// saves our data
function frontpage_save_meta_box_data( $post_id ){
    // verify meta box nonce
    if ( !isset( $_POST['frontpage_meta_box_nonce'] ) || !wp_verify_nonce( $_POST['frontpage_meta_box_nonce'], basename( __FILE__ ) ) ){
        return;
    }
    // return if autosave
    if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ){
        return;
    }
  // Check the user's permissions.
    if ( ! current_user_can( 'edit_post', $post_id ) ){
        return;
    }
    // manufacturer url string
    if ( isset( $_REQUEST['manufacturer-url'] ) ) {
        update_post_meta( $post_id, '_manuf_url', sanitize_text_field( $_POST['manufacturer-url'] ) );
    }
    // store custom fields values
}
add_action( 'save_post_page', 'frontpage_save_meta_box_data' );

error code: 523