Set value after alert (Notification)

I am trying to set up a sms notification every day after due date has passed in sales invoice. I have set these options.

The problem is, this is triggered only 1 day after due date and it does not repeat.

I thought of using this field

and changing the due date in sales invoice by this field.

How can I set the date to “today” in this field ?

Best of my understanding, you can also update a value in this field for which “Allow on Submit” property is checked. Perhaps you should enter a separate field as Due Date is standard field in which value is already set based on back-end code like Lead time or Payment Terms offered to the customer.

Thank you for the insight.

Will definitely add a new due date field.

But how to actually get and update today’s date from “set property after alert”