Requirements
This step requires that a MTA already exists. Please refer to Add a MTA
Steps for adding a Phonenumber
Go to VoIP > MTAs
Choose a existing MTA and open the Edit-Page. On the right side click on the Plus-Button under "Assigned Phonenumbers" for creating a new Phonenumber.
Fill out all the required fields to create a new Phonenumber.
Next Add a PhoneTariff