MailChimp/PopUp plugin not working

I'm trying to show a popup to allow people to sign up to our MailChimp newsletter (using MailChimp integration), but it's not working. The only condition is that a user must come from a search engine, but when I try to access the website from either Google or Bing, no popup shows, whether I'm in incognito mode or not and using both Firefox and Chrome.

I've tried the default AJAX loading method and the footer loading, but nothing interesting happens when I use either.