place order error page using cardsave gateway

Hello,

I am having a problem when I am integrating the cardsave payment gateway to the woocommerce plugin.

On the checkout page, I review my cart and select place order and the following error appears:

{"result":"failure","messages":"

    \n\t\t\t
    Action failed. Please refresh the page and retry.<\/li>\n\t\t\t
    First Name<\/strong> is a required field.<\/li>\n\t\t\t
    Last Name<\/strong> is a required field.<\/li>\n\t\t\t
    Address<\/strong> is a required field.<\/li>\n\t\t\t
    Town\/City<\/strong> is a required field.<\/li>\n\t\t\t
    Postcode<\/strong> is a required field.<\/li>\n\t\t\t
    Country<\/strong> is a required field.<\/li>\n\t\t\t
    Email Address<\/strong> is a required field.<\/li>\n\t\t\t
    Phone<\/strong> is a required field.<\/li>\n\t\t\t
    First Name<\/strong> is a required field.<\/li>\n\t\t\t
    Last Name<\/strong> is a required field.<\/li>\n\t\t\t
    Address<\/strong> is a required field.<\/li>\n\t\t\t
    Town\/City<\/strong> is a required field.<\/li>\n\t\t\t
    Postcode<\/strong> is a required field.<\/li>\n\t\t\t
    Country<\/strong> is a required field.<\/li>\n\t\t\t
    Invalid shipping method.<\/li>\n\t\t\t
    Invalid payment method.<\/li>\n\t<\/ul>","refresh":"false"}

I tried adding a paypal account which all works fine. The issue only occurs when I select the cardsave payment type.

Any help much appreciated

http://wordpress.org/extend/plugins/woocommerce/