You can use the relay service to retrieve messages from voicemail or answering machines.
Voicemail Retrieval:
When you request the relay operator to retrieve messages from a voicemail system, the relay operator will follow your instructions for dialing, pin entry, access codes, and/or system commands to retrieve new messages, play messages, save, and/or delete messages.
Answering Machine Retrieval (AMR):
When a you request the relay operator to retrieve messages from an answering machine at your location, simply type “AMR GA” then follow the instructions from the relay operator.