Hi,
There are two things here:
- You activated the "force canonical URL on products listing" setting of the HikaShop configuration. So the canonical URL of the product is used on the listing instead of the dynamically generated URL. Sometimes, this is not necessary and turning off that option would definitely help.
- You also set a canonical URL for the product, but apparently only for the main product, not for each translation of the product.
Being able to translate the canonical URL has been added with HikaShop 2.6.0 so with the 2.5.0, you don't have it and thus it always uses that URL. The system should add the /en in the URL. You should enter the full URL, including the language tag in the canonical URL for each language.