Accepted Solutions
Hailey is right, here is the URL with more details.
Allowing Users to Access Cisco Unity Connection by Phone Without Entering a PIN
By default, users are prompted for a PIN before they can sign in to Cisco Unity Connection to check messages or change their personal settings. As a convenience to users who often access Connection from a mobile phone, home phone, or phone in a secured office within your organization, you may consider specifying that Connection should not prompt them to enter a PIN when they call Connection to access their mailbox from their primary extension or alternate devices. (When they call Connection from an unknown extension, Connection prompts them for their PINs as usual.)
For security reasons, it may not be appropriate to allow users who work in shared workspaces, cubicles, or other public areas in your organization (such as a lobby or reception area) to access Connection by phone without first entering a PIN.
Users who do not have to enter a PIN to sign in to Connection are still prompted to renew their phone PINs when they expire.
To Allow Users to Access Cisco Unity Connection By Phone Without Entering a PIN
Step 1 
In Cisco Unity Connection Administration, find the user account or template that you want to edit.
Step 2 On the Edit User Basics or User Template Basics page (as applicable), check the Skip PIN When Calling From a Known Extension check box.
Step 3 Select Save.
Thanks
Mudassir
Hailey is right, here is the URL with more details.
Allowing Users to Access Cisco Unity Connection by Phone Without Entering a PIN
By default, users are prompted for a PIN before they can sign in to Cisco Unity Connection to check messages or change their personal settings. As a convenience to users who often access Connection from a mobile phone, home phone, or phone in a secured office within your organization, you may consider specifying that Connection should not prompt them to enter a PIN when they call Connection to access their mailbox from their primary extension or alternate devices. (When they call Connection from an unknown extension, Connection prompts them for their PINs as usual.)
For security reasons, it may not be appropriate to allow users who work in shared workspaces, cubicles, or other public areas in your organization (such as a lobby or reception area) to access Connection by phone without first entering a PIN.
Users who do not have to enter a PIN to sign in to Connection are still prompted to renew their phone PINs when they expire.
To Allow Users to Access Cisco Unity Connection By Phone Without Entering a PIN
Step 1 In Cisco Unity Connection Administration, find the user account or template that you want to edit.
Step 2 On the Edit User Basics or User Template Basics page (as applicable), check the Skip PIN When Calling From a Known Extension check box.
Step 3 Select Save.
Thanks
Mudassir
