$wpdb->insert, need help…

This data isn’t being updated in the database, can someone help me understand why?

elseif (isset($update_this_slideshow_button)) {

	global $table_name;
	global $id;
	global $title;
	global $category;
	global $max_slides_to_display;
	global $theme;

	$wpdb->insert( $table_name, array( 'title' => $title, 'category' => $category, 'max_slides_to_display' => $max_slides_to_display, 'theme' => $theme), array( 'id' => $id ) );

	$successfully_updated_message = '<div class="updated"><p>' . $title . ' has been updated.</p></div>';

}