Currently on my Webex, can call over PSTN via Local Gateway >> CUCM. For restriction calls cannot be done by CUCM because CUCM only forwards calls from webex via local gateway to PSTN. therefore for restriction calls I do in webex, each user will have a different call privilege. When i go to outgoing call permission, the setup only this :

What do I need to do if I want to give a certain access call to one of the extension numbers like in CUCM there is a CSS that handles restriction calls?