How to setup the primary contact name and email address on clients details via API?
I already tried setting up the primary contact email but the details was not added when getting the clients details.
Thanks for getting in touch! You can see the details of setting those values here: https://www.campaignmonitor.com/api/clients/#client_details. There are included options for primary contact name & email (see here: http://d.pr/IJrk). I hope that helps!