Reducing price to 0 not works

-- url of the page with the problem -- : www.politikchronist.org
-- HikaShop version -- : 4.6.0
-- Joomla version -- : 3.10.9
-- Error-message(debug-mod must be tuned on) -- : Notice: Undefined property: stdClass::$order in /var/www/html/joomla/media/com_hikashop/mail/payment_notification.preload.php on line 230

Notice: Trying to get property 'order_status' of non-object in /var/www/html/joomla/media/com_hikashop/mail/payment_notification.preload.php on line 230

Due to the ongoing Ukraine Crisis we wanted to reduce the price for our Ukraine books in digital form to 0 Euro. But after the order which seemed OK, the following error message appears:

Notice: Undefined property: stdClass::$order in /var/www/html/joomla/media/com_hikashop/mail/payment_notification.preload.php on line 230

Notice: Trying to get property 'order_status' of non-object in /var/www/html/joomla/media/com_hikashop/mail/payment_notification.preload.php on line 230

Thanks for any information.
UPDATE
For the client it seems that the download link appears in the e-mail and that he can download the book without problems. It is just the error message to the admin I think.

Hi,

There is a wrong copy/paste there. Instead of: the line should be: We'll add that fix on our end too. Thanks !

So I mean, I just can wait for the next update, no need for immediate correction from my side because it's nothing serious? I have limited Internet in the moment because of my traveling to Africa, therefore I try to avoid unnecessary internet connection

Hi,

Yes, no worries. That's just for the payment notification and it's just a wrong copy/paste. You can ignore it for now.