Change post status to private

Hi,

I would like to update the post status of Flamingo posts to private so I can more securely use them with WordPress’s REST API. I have tried to do so with wp_transition_post_status but this does not seem to make a difference? Please assist.

function flamingo_inbound_status($post) {
	$post_type = get_post_type ($post);
	$old_status = $post->post_status;
	if ($post_type == 'flamingo_inbound') {
		$old_status = $post->post_status;
		wp_transition_post_status('private', $old_status, $post);
	}
}
add_action( 'transition_post_status',  'flamingo_inbound_status', 10);

Many thanks,

Costa

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