Amazon alert: Book not available

When is the "Book not available" alert triggered?

As soon as a book is no longer available, this alert is triggered.

What additional information does the alert provide?

There is no additional information for this alert.

For whom is the alert available?

The alert is only available for vendors.

How do I activate the alert?

Under "Settings / Alerts", go to the alerts that are already available and activate the corresponding alert "Book not available" under "Select alert types".