Be able to turn off automatic email notifications for new or existing appointments.

For some reason I can't "turn off" the automatic email notification feature that notifies me when there is a "reminder" for an appointment. I have tried to cancel it in Google Calendar, but it doesn't work. 

I don't see it as an option in your calendar app to not have an automatic email notification sent to me. Plz offer this soon, as this creates duplicate work to receive the notification on my phone and then to have to delete the email notifications manually. Thanks, Karen