Caller ID is a facility that identifies and displays the telephone numbers of incoming calls made to a particular line. The Admin can use their Inbound Number as Caller ID so that if a lead calls back, it will be routed to the correct agent(s).  A good practice is to rotate your caller ID so the number does not get stale.  

From the Dashboard, click on Call Center and select Campaigns from the drop down.

In Show Campaigns, click on Action button and select Settings from the drop down.

Select the Caller ID from the drop down. 

Note: Caller IDs listed in the drop down are the Inbound Numbers added into the account. Due to FCC ruling, you cannot use a phone number as CID if it is not assigned to your account.

Click on Apply Changes.