Subscription widget not submitting

I installed Jetpack subscriptions on a site and placed the subscription widget in the primary sidebar. On submission of the form, the page simply reloads and no confirmation email is sent. I went into the theme and called the Jetpack_Subscriptions::subscribe($email) function and that worked properly. Any advice on how to further troubleshoot this would be greatly appreciated.

https://wordpress.org/plugins/jetpack/