Next button issue

Hello,
I am experencing similar problems with a new site I am working on.
see below: ouaganet.com

Hi
You are using an old version of the extension. Please reply the support ticket so that I can assign order to your account .

I have an urgent work at my family, so I have to go home now without internet connection . I will check and fix the issue for you when I come back to my office (for 30 hours from now) .

Thanks,
Tuan