Let's say you want to configure a notifier, so that everyday it will run automatically and it will only send 1 email to the customers whose orders are unfulfilled for 15 days and after sending the email, it should not send email for the same order going forward. To do the same, follow the below steps:
1. Click on Add-New-Notifier button to create a Notifier
2. Configure include-exclude of unfulfilled orders range to 15-16 (1 day gap) days as shown below
3. In notification section, Set Send-email-to-customer
4. Set frequency to run the notifier every day
5. Click on Save button
That's it. Going forward let the notifier send the delay order notification for your customers.
How does it work? Notifier will be triggered as per frequency setup (once every day as per above setup). It will find all the order unfulfilled under 15-16 days. This way every order unfulfilled for 15 days will be caught only once by the notifier and email will be sent to the customers of orders 1x at the 15 day marker.