[Plugin: Mailchimp Widget] Shortcode not working

Hi,

I just made a website live, which uses the plugin, but the shortcode does not work. This is a link to the page;

http://www.ducklingfarm.com/contact-us/

You can see on the right side there’s a box entitled “Join Us,” and the shortcode is showing up instead of a form.

Please help.

Thanks,

Jaeeun