Canonical URL and Multi-domain

Hi,

First, I see two canonical URLs on your product pages.
So you should fix that.
One must come from HikaShop (the one you specified in the product), the other, another extension.

Second, a canonical URL with just the alias of the product is not normally valid.
You should normally have the menu item alias in the URL, unless the menu item is the homepage, but it doesn't seem that your home page is a products/categories listing menu item.
So actually, even domain.com/virtual-number-algeria should result in a 404.
It works but I don't know why. You must have done something else you didn't say in order to have that to work, and what you did is probably done only for the main website and not the other domains.
But it's hard to say much more.
One thing is sure: HikaShop doesn't change the domain name for the canonical URL.
If you are on the .pt website, the canonical URL will be with .pt domain name.
HikaShop adds the domain name to the text you specify in the canonical URL field by asking Joomla what the current domain name is. It does that by calling the function JURI::base() of the Joomla API which returns the current domain name:
docs.joomla.org/API15:JURI/base
That's unless there is some other extension messing with the URLs in some way.

Hi,

As I said, it's not HikaShop which does that.
Please make sure that the live_site setting of your configuration.php is empty or always contains the URL of the current domain name.
Please also check your .htaccess as to not have redirects on the different domain names.
Finally, check the other extensions you have. The first thign to check here are the system plugins. Try deactivating them one by one and refresh the cache and access the homepage and try the process again each time to see if it solves the problem until you the plugin causing that issue if any.
These are only guesses of the most probable things I could think of.