How can I use page.php?

Hi, thanks for the nice plugin.
I am having trouble with single.php being applied.

I have turned on the “Page Attributes” in the “Support” section of the settings page.
However, the template “single.php” is applied.
(Checked with plugin QueryMonitor)

I would like to use page.php.
What settings do I need to change?

function cptui_register_my_cpts_contents() {

	/**
	 * Post Type: MyContent.
	 */

	$labels = [
		"name" => __( "MyContents", "astra" ),
		"singular_name" => __( "MyContent", "astra" ),
	];

	$args = [
		"label" => __( "MyContent", "astra" ),
		"labels" => $labels,
		"description" => "For Members",
		"public" => true,
		"publicly_queryable" => true,
		"show_ui" => true,
		"show_in_rest" => true,
		"rest_base" => "",
		"rest_controller_class" => "WP_REST_Posts_Controller",
		"has_archive" => false,
		"show_in_menu" => true,
		"show_in_nav_menus" => false,
		"delete_with_user" => false,
		"exclude_from_search" => true,
		"capability_type" => "post",
		"map_meta_cap" => true,
		"hierarchical" => true,
		"rewrite" => [ "slug" => "contents", "with_front" => true ],
		"query_var" => true,
		"supports" => [ "title", "editor", "thumbnail", "page-attributes" ],
		"show_in_graphql" => false,
	];

	register_post_type( "contents", $args );
}

add_action( 'init', 'cptui_register_my_cpts_contents' );