Is there a user id that is not the user's email address?
In Zendesk users are provided with two types of id's, not related to the email address: the
user ID and the
id of a user is part of the URL of a user's profile:
User id's are also available via the User API:
external_id is a unique identifier coming from another system, that allows mapping between Support and third-party integrations. Like the
id, this attribute is also available via the API, and
null by default.