Hi,
I see a completely blank page on your link.
This indicates a fatal error is happening.
Activate the "debug" setting of the Joomla configuration and try again.
You should hopefully see an error message on the page which will help us tell you what to do.
It's likely due to PHP 8.4. If the template has old view overrides of HikaShop, it might have code which isn't made to work with PHP 8.4 and that we changed in our end but that your template's old view overrides are still using. The error message should make this clear once the debug is activated.