No categories showing in back end

-- url of the page with the problem -- : goldfieldfireworks.com/administrator/ind...kashop&ctrl=category
-- HikaShop version -- : 6.5.0
-- Joomla version -- : 5.4.6
-- PHP version -- : 8.2.31
-- Browser(s) name and version -- : Firefox 140.12.0esr (aarch64)

In the back end, each of my products has a category assigned. But when I go to Hikashop -> Categories, there are no categories showing. Even if I click the "Rebuild" button and I get the message "The category tree has been rebuilt," there are still no categories. Please see the screen shot.
Thank you for your help with this!