To save a voicemail locally use the web portal:
1. Go to your account at myonecloud.com and log in.
Note: If you are an office manager or reseller, you’ll need to log in, click your name in the top right, and then select My Account from the drop-down.
2. Click on Messages from the navigation.

3. Locate the Voicemail you’d like to download, then press the Download button associated with the voicemail as shown below.
The file will download and save to your computer (per your computer settings). You can now keep that voicemail locally for as long as you wish!