Accessing user API, which is enabled on the local network.
switchvox.users.getMyInfo works, while switchvox.users.phonebooks.entries.add does not. Returns the error " was not found"
Building API calls with the Test Suite, relatively confident that the calls are correct.
Switchvox is a Sangoma commercial product. You need to obtain support from their commercial web site, not the open source community.
You should go to this comminity, then search for a suitable question or raise a new one in the section Commercial Products and Partners -> Sangoma.
Switchvox is not FreePBX. They want https://www.digium.com/support/switchvox
The page seems to still have Digium branding.