wc-kco-date-of-birth-mandatory.php

/**
 * WooCommerce - Klarna payment gateway
 * Filter Create order for making date of birth a mandatory field in Klarna Checkout iframe.
 **/

// New order ($create)
add_filter('kco_create_order', 'my_kco_create_order');

function my_kco_create_order( $create ) {
	$create['options']['national_identification_number_mandatory'] = true;
	return $create;
}