The Field Email Notification must be filed with the email that will be notified. what might be causing this error.
Firstly the content is the Iframe Facebook pattern, can not be changed except by style (dark and light),
About the error in the sending, I checked and saw that is experiencing an error while sending the email, could certify that you are using the latest version of the plugin, and if the e-mail plugin configurations are met. because the 500 error is very generic.
If you continue to sending error, please contact us again.
