Error 404 on English website checkout

-- url of the page with the problem -- : www.chatelsensations.com/ski/index.php/e...11-am-5-or-6-lessons
-- HikaShop version -- : 2.6.1
-- Joomla version -- : 3.4.8
-- Browser(s) name and version -- : Mozilla

Hello all,

I have a problem that I cannot solve. I have created a website in 2 languages (main language is French and secondary is English). I don't use Falang or any other module for the translation as they were not working as I wanted.

The French website works perfectly. However, on the English website, I can access the pages with the products, but I cannot proceed to checkout (error 404). I don't understand why because a few weeks ago, it was working perfectly. I updated the language file, but it does not chane anything.

What can I do?

Here is one of the pages : www.chatelsensations.com/ski/index.php/e...11-am-5-or-6-lessons

Thanks a lot,

Thank you so much, that worked just perfectly!