MailChimp Integration

Hello there! I spoke to Katya earlier and she kindly recommended a plugin for importing data into Mailchimp from Contact Form 7.
I've completed the matching of fields and created a webhook, however when I submit the form (you'll find the new one at http://www.makemesparkle.co/example)
The old one is also on the page with the footer, however that one has stopped working now too. You can get as far as completing the form, however after submission, it seems to time out. Thanks

Rachel