Hi,
It probably comes from some customization.
Check if you have the folder templates/YOUR_TEMPLATE/html/com_hikashop/
If so, rename it temporarily to something else and it will deactivate all the view overrides for HikaShop.
If then the products display, it will confirm this theory. Then you need to rename each sub folder to identify which sub folder the file with the issue is, and then each file in the sub folder you'll have identified to find the file which is the culprit.
There is a high chance that it comes from the templates/YOUR_TEMPLATE/html/com_hikashop/category/listing.php view file.