Call Handling API scope/license requirements

Phone
1

I am trying to set up a powershell script to update call handling on multiple phone lines. In the event that our external number (MAS Comm) goes down, I want to be able to change the call handling to a separate external number (personal cell). I can do this easily in the web portal GUI, but attempting to do so via the powershell script is failing due to ‘extension doesn’t exist’ message. As best as I and our zoom account rep can figure, this is due to the workplace/phone plan license requirements. What are the minimum license requirements to get this to function as needed? We currently have tried zoom workplace pro and business with zoom phone basic (us/ca unlimited package). I am not seeing the scope I apparently need for this to work (phone:write:admin / phone:read:admin) with this config.