When you create the first phone system integration, this first phone system is automatically selected in the default user template. The users that you add after creating this phone system integration are assigned to this phone system by default.
However, for each additional phone system integration that you create, you must add the applicable new user templates that assign users to the new phone system. You must add the new templates before you add new users who are assigned to the new phone system.
For details on adding new user templates, or on selecting a user template when adding a new user, see the “User Templates” section of the “User Attributes” chapter of the System Administration Guide for Cisco Unity Connection, Release 12.x, available at https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/12x/administration/guide/b_12xcucsag.html.