Subscription doesn't go through after hitting submit

Hello,

I can’t get Easy Mail Chimp to work on one of my sites (http://thesfile.com). When I submit after entering the required fields, the page refreshes, but nothing happens. There’s no “thanks for subscribing” message, and no user info is added to my Mail Chimp list. I updated my plugin and am now using 5.4.3.

Any ideas as to how I can get it up and running? Thank you in advance.

https://wordpress.org/plugins/yikes-inc-easy-mailchimp-extender/