Membership Registration Does Not Work

I have an issue on my website. I new members are unable to complete the membership registration I get an email from the site that a new member registered after entering a user name and password. Then, the process stops. No payment or confirmation pages ever show up.

People are able to register, but they never get the to final payment and completion process. Can someone on your staff take a look at this for me. on the front and back end of my site.

I have an event coming up where over 100 people will need to sign up and receive their 30-day membership trial period and I need this to work again. It has stopped working and I don't know why.

My website URL is http://www.shinshuri.com

Thanks,
Shinshuri