My first guess is that you haven’t defined the Notification type and throws an undefined error somewhere:
Guess #2 is that the I18n text hasn’t been defined in
Depending on what you want to share with the user, I’ve found it’s sometimes better to send a PM and then spell out what happened in more detail.
Edit: Just realized there’s a
custom notification type (14) which you are using. So #1 is out.