Doesn't show error message

Hello,

Thanks for the great plugin. I am having problem of an error message. Even though visitor does not enter email address, submit button still works. Normally, it should give an error message but it doesn’t work.

My blog is http://www.diyeton.com/blog

I also can’t make popup work.

Thanks in advance for your help,

Enes

https://ww.wp.xz.cn/plugins/mailchimp-wp/