Checkout does not stay translated

When i click checkout button it is translated in Chinese but then there is a loading circle and it changes back to English even though the sites language is set to Chinese and everything else is translated. It just seems to reload and change the language. It also does it for the confirmation page.

Any help would be greatly appreciated as this is very frustrating when everything else translates properly apart from the very last steps.

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