Hi @LynseyLeonard, thanks for a good question. You can access voicemail via the phone as long as you have:
A number associated with the Check Messages interface within your Call Routing
The Entity has a UserID within their account details.
To find your Check Messages number go to Platform > System Integration > Call Routing (as shown).
Find your Check Messages number - This is what mine looks like
Next, the account will need a UserID (typically the extension number). Go to the Entity and Edit the Account Information to view or set this. Here is mine (data obfuscated for security). - Default system PIN would be 0000. If you have forgotten this, then please use the Reset Pin button.
Then Dial into the number, enter your UserID, PIN and listen to the instructions.