Thanks @gianni.zoom for the reply. What permission is needed for downloading voicemails? We are using API (https://api.zoom.us/v2/phone/voice_mails?) with bearer token to get list of voicemails. We are using the same token to download the voicemail.
The prereqs on each API endpoint page share the account type and scopes needed which helps clarify permissions. E.x. whether only an admin with the specific scope will be able to retrieve info via that endpoint.
Please look at the detailed response documentation as well.