Digital Passport offers an online identity to users. It is a login method that is bound to a device rather than a person and is used for a secure login without the need of a username and password.
Digital Passport is a form of authentication that no longer will be used and will be obsolete in the near future. Since a Digital Passport is matched with a device, rather than a person, it is considered to be not up the required standards of security. eHerkenning will take the place of Digital Passport and the transition is going on right now.
You can read more on how the insurance companies are making the switch in this article (in Dutch).