"Users is no longer available as a resource. In order to see information and take action on users, you should use the Contacts API."

"Contacts (for Leads only) is no longer available as a resource. In order to see information and take action on leads, you should be using the Contacts API."
Documentation referece

Using intercom.users.find now returns a 400 error, and the user.leads.find function automatically searches for Leads only making it impossible to search for users on the new API.