Controlling who is able to place calls from a phone number. – Tresta

To control who is able to place calls from a Tresta phone number, you’ll need to sign in to the web app, where you can edit the phone number.

Note – if you are not a member of the System Admins group, you will not see this option.

Select Phone Numbers from the sidebar options on the left, and click the Edit icon on the phone number that you want to modify.
On the Edit Phone Number screen, select the Outbound Calls tab.
To grant dialing permissions to any user who is receiving calls from the number, select “Inherit dialing permissions from the Inbound Calls tab”.
Or, to manually grant dialing permissions, select “Manual” and add the list of users and groups that you want to be able to place calls from the number.