Hello,
Your issue is coming from the fact that you didn't have added the "USER POINTS" step on your checkout workflow via "Hikashop->System->Configuration->Checkout" after having activated the "Use virtual coupons" option through your user point payment method configuration page.
As explained through the documentation :
If you want to go further with the user points, we will recommend you to access to configuration of the "HikaShop user points" plugin in the Joomla plugin manager.
Thanks to it, you will be able to activate some specific features like a new "checkout workflow step" which can display to the customer the number of points he got and allow him to use or not his points to create a discount. After activating the checkout workflow step, you can add it to the "Checkout Workflow" setting of the HikaShop configuration page.
www.hikashop.com/support/documentation/257-using-points.html
Kind regards,
Mohamed Thelji.