Hi,
Thank you for the report. Joomla 4.1 changed the way the javascript files are included on the page, which creates a problem with the way HikaShop's AJAX system is working.
To fix the issue, the line:
result[1] = result[1].replace(/\.js\?[0-9a-f]{32}/gi, '.js');
has to be changed to:
result[1] = result[1].replace(/\.js\?[0-9a-f\.]{1,128}/gi, '.js');
in the file media/com_hikashop/js/hikashop.js
We've included the modification on our end so you can just redownload HikaShop 4.5.0 on our website and install it on yours to get the patch.