Enter coupon and get 404 page

-- HikaShop version -- : 2.6.3
-- Joomla version -- : 3.5.1
-- PHP version -- : 5.4.24
-- Browser(s) name and version -- : Chrome 41.0.2272.118

Hi,

We are currently having an issue with Hikashop entering coupon in the checkout.

We installed AWO Coupon Pro V: 2.4.8 pro and created a post in their forum, which they believe is to do with Hikashop.
awodev.com/forum/awocoupon/help-section/...ode-and-get-404-page

When we get to the checkout page, we enter in the coupon code in the coupon field and click onto the add button and it takes you to a 404 page, even if a coupon doesnt exist and click add, takes you to a 404 page.
This is if we are logged in or not logged in.

On the site we are using HikaShop Business: 2.6.3, which is the latest version along with latest version of Joomla 3.5.1

Hope you can help.

Hi,

Thank you, currently looking into the issue.

I believe some custom code on our end has been added which maybe causing the issue.