Get billing first name in export

Hi there,

I use Woocommere with the Events Calendar Plugin and I have the following problem:

When I try to export some attendee information I’d also like to include the user information like first name, last name, address and so on.

For this I have the following code which doesn’t work:

$order = new WC_Order( $item['order_id'] );
$name = $order->get_billing_first_name();

The problem occurs with the second line, the first line works fine with some other code.

Could someone please help me where my fault is?
Many thanks in advance!