I read the article Creating and using customer lists but I am unable to locate this within my account. Why can't I create customer lists?
Customer lists are part of the Customer Lists & NPS Surveys add-on. If you are on the Zendesk Support Professional or Enterprise plans, you can purchase this feature.
For pricing and purchasing information about this add-on, contact our Sales team.
To learn more about the different add-ons Zendesk offers, visit About Support add-ons (Professional and Enterprise).