The file the form is sending to is currently,
When it should be something like this
Here is the code which grabs that URL,
<input id="submitUrlWidget" type="hidden" name="submitUrlWidget" value="<?php echo get_template_directory_uri() . '/lib/includes/submit-widget.php'; ?>" />
But as you can see it is different from yours, have you done any customizations? Try deactivating all of your plugins to see if this solves it.
EDIT - Looks like the test email went through. For future reference let us know which host you are using and whether you installed Wordpress manually or had them do it.