The default free voicemail feature has 15 voicemail storage capacity with no transcription.
Enhanced Voicemail: Get 100 voicemail storage capacity and audio to text transcription services for $4.99/mo. The transcription along with audio file is delivered to the user’s email and it also available in iPlum portal.
Login: Go to the web page https://my.iplum.com on your computer or a tablet.
Accounts || Click iPlum Login ID of the User || Manage Plans || Voicemail Box || SETTINGS
Click “Change Voicemail Plan” and follow the prompts to select the new plan.