Amazon Add-to-cart button Issue

-- url of the page with the problem -- : itta.ca/shop/index.php/test-product/product/2-4652-tow-truck
-- HikaShop version -- : HikaShop Starter 2.2.3
-- Joomla version -- : 3.2.2
-- PHP version -- :5.3.3
-- Browser(s) name and version -- : chrome 32.0.1700.107, firefox 26.0
-- Error-message(debug-mod must be tuned on) -- : Product not available, The cart is empty

i just started trying to do prove of POC between hikashop with joomla and two other e-com product, today i download the startup version and added couple of product, overall feeling of the product is very good. One thing, i noticed when i try to insert the amazon add-to-cart link to product, it reports the Product not available, The cart is empty. but when i add the html button code to joomla article it can click and redirect to amazon page.. just wondering if there is any workaround to this, also if there is way add to cart to hikashop shopping cart and then check out from amazon. thanks,

And i don't think this has anything to do with the free version we are using, right?

thanks for the prompt response, add-to-cart button is offer by amazon, below are the sample code.

<form method="GET" action=" www.amazon.com/gp/aws/cart/add.html "> <input type="hidden" name="AssociateTag" value="storeid-20"/> <input type="hidden" name="SubscriptionId" value="[AKIAJ6S4IJDOPGH25TNA]"/> <input type="hidden" name="ASIN.1" value="B00003CWT6"/><br/> <input type="hidden" name="Quantity.1" value="1"/><br/> <input type="image" name="add" value="Buy from Amazon.com" border="0" alt="Buy from Amazon.com" src=" images.amazon.com/images/G/01/associates/add-to-cart.gif "> </form>

Job well done to drive away potential customers.. thanks anyway.