Any Cisco Jabber calls you can't answer gets sent to voicemail so the person can leave a message. To set up voicemail, you'll need to get your voicemail account information from your administrator.
Before you begin
Get your account information from your system administrator. For Voicemail accounts, you need a username, password, server address, and in some cases, a port.
On the Settings screen, under Accounts, tap Voicemail.
Enter the account information that your system administrator provided.