使用Realex HPPrequest保存客户名称

I'm using the realex payment gateway (https://developer.realexpayments.com/#!/hpp/getting-started) and am redirecting to their hosted payment page to process payments.

My problem is that I can't find how to save the customer name in the right fields as they appear on the payment dashboard/transaction details page (red rectangle on screenshot below).

I've done some research and have tried adding supplementary data like the code below, but it still doesn't make the customer name appear on the transaction details page (it only appears as an autofill value to the cardholder name on the payment form).

$supplementaryData = array("HPP_CUSTOMER_FIRSTNAME" => "James", "HPP_CUSTOMER_LASTNAME" => "Mason");
$hppRequest->addSupplementaryData($supplementaryData);