USPS shipping amount error

-- url of the page with the problem -- : maus.development.kandytech.net/
-- HikaShop version -- : 2.5.0
-- Joomla version -- : 3.4.1
-- PHP version -- : 5.5.24
-- Browser(s) name and version -- : Mozilla Firefox 38.0 (linux)

Hi,
I'm using USPS shipping method for my shopping cart,and it's not updating shipping value.
for a example if use 1 product it shows me a price
if add 20 more products the shipping price isn't changing.

Shipping Details: maus.development.kandytech.net/shipping

My shipping plugin configuration attached.

Can someone help me?

Dilum

Hello,
Can you show me how did you configured the product that you have in your cart ?
Thanks.