Infinite loop on checkout

[CloudCyberSystems]

Hi guys just looking over a friends prestashop website and it seem to have an infinite loop on the checkout. 

Can anyone spot any issues?

To replicate the issue follow these steps

www.laddersukdirect.co.uk

(create an account and log out of it)


Add an item to the basket.

press checkout from the basket (top right under header menu)

Login with your created account

Follow checkout process

Select "Pay with Visa, Visa Debt........" 

and it will just loop the page "http://www.laddersukdirect.co.uk/modules/sagepay/validation.php"

he is using PrestaShop™ 1.4.0.17

[CloudCyberSystems]

We found the issue.

some of the address information was incorrect this solved the issue