MailChimp widget not working

I can’t seem to get the MailChimp widget to work on my homepage. Looks like it is all OK, I enter an email address to test it out and it just refreshes the screen and leaves the email address in here.

Have entered the API key successfully. Have installed another temporary measure in the meantime but it’s not what I want to leave in position. Is anyone else having this issue please and how do I fix please?

I am using the Vantage WordPress theme which has a drag and drop editor for styling the homepage which means I can’t edit code. I can only drag and drop the widget into place – all of which seems to be working fine until you try to actually use it. The site is in maintenance mode still so not sure you’ll be able to see it but it’s at mwcommunications.com.au

I need to launch this site tomorrow 6 November 2013 so urgent help appreciated.

Thank you.

https://www.ads-software.com/plugins/mailchimp-widget/