If your administrator has set up your profile with multiple lines with different phone numbers for calling, they appear in the desktop version of your app. You can switch lines if you need to make outgoing calls from different lines, such as a front desk line, support team line, or an individual line with a different caller ID.
Multiple lines only work directly in Webex App.
Go to your active line and then choose a different entry from the list.
The lines are easily identifiable by the associated phone numbers and descriptions.
After you make your selection, every outgoing call you make uses your new active line. You can change the active line again at any time.