Once the end user has more than one registered contact channels, you can change their preferred contact channel on behalf of them.
Parent topic:Update a User’s Details
Preferred Contact
The preferred contact channel is a user’s primary point of contact to receive all Digital Identity Management-driven notification messages.
When a user first onboards with their email address or mobile number, that address or number is set as their preferred contact channel by default. If the end user registers additional email addresses or mobile numbers to their Digital Identity Management end user profile, they have the option to change their preferred contact channel as needed.

