Can I add a non-E.164 number to an internal contact?
Yes. Under certain circumstances, such as working with SCIM clients, you may need to add a non-E.164 number to support call transfers across phone trunks to external platforms, such as Microsoft Teams, Zoom Phone, and others. To do so, you can use Azure, Active Directory, or SCIM to populate the Other Phone field on a user profile with a non-E.164 number.
For more information, see Configure the Microsoft Teams integration or Configure the Zoom Phone integration.