Hi,
The system will automatically use the canonical URL on all the products listings displayed by HikaShop.
If you don't see the canonical URL on some of the products listings, it's either:
- that they are not hikashop products listings (which I don't think apply here right ?)
- that there is some caching activated on the website preventing you from seeing the change (check that you don't have any caching activated, or clear it)
- that you're not using the normal SEF system of Joomla but a third party SEF extension which uses its own system for SEFing URLs (it could be the case here so please check on that)
- you had edited views of Hikashop from a previous version of HikaShop which didn't support canonical URLs on listings via the menu Display>Views (it could well come from that and in that case, removing the customization of the product views and reapplying your changes to the new version of the view files would be a solution)
- in a similar manner, your template came with HikaShop overrides for an old version of HikaShop.
In both last cases, an easy way to check that is to see if you have the folder templates/YOUR_TEMPLATE/html/com_hikashop/product and if you do, rename it via FTP. That will disable all the product view overrides and you can see if you get the new URLs on the listings.