If there is no Leave Voicemail disposition appearing in your dial session in Salesforce, it may be because you haven't setup a voicemail yet. PhoneBurner will not show a Leave Voicemail disposition if no voicemail has been setup. To setup a voicemail follow the steps below.
1. Navigate to the PB App in Salesforce
2. Click the Voicemail tab
3. Follow the on screen instructions