Problem on Captcha on "Email" option

I am trying to email this form (testing it), I click embed form - email & when i enter the challenge words i keep getting an error message.

Unfortunately, I'm unable to reproduce the problem. Have you tried using a different web browsers? The captcha usually appears to prevent spams and bots to send an email, although I'm not sure why it is not proceeding in your end. 

You could also send the form's URL or direct link by copying and pasting it in your email client.

You can get your Form URL/direct link in the Preview window.

Or you can also get it in the "Embed Form" options.

Do let us know if that works.