One vendor in the cart: no warning displayed

-- url of the page with the problem -- : localhost
-- HikaShop version -- : 2.5.0
-- HikaMarket version -- : 1.6.4
-- Joomla version -- : 3.4.3
-- PHP version -- : 5.5.9-1ubuntu4.5
-- Browser(s) name and version -- : any browser

Hello!
I'm trying to use hikamarket multi-vendor and have a such issue:
I choose the limit of the vendors in the cart as "One vendor". When I try to add to cart an item of the second vendor, it is not added, but I receive a pop-up window about successful adding. If I switch to the cart mode "forward to checkout" and try to add second vendor to the cart, I get error 404. Please, help me. how to configure Hikamarket or Hikashop to get a warning as at your demo site ("You can't add item A of vendor B").
Thank you!

Hi,

Are you sure that the popup is not because you already have the parameter "?popup=1" in your current URL ?
With the "redirect to checkout" ; is it working when you add the first product ? What URL do you have ? Does your "force menu on checkout" right configured ?

In order to tell you what you have to change in your configuration, first we have to know your current (HikaShop mostly) configuration.

Regards,

Thank you for the support, the problem is solved, but I hae forgotten the reason, sorry.