To resolve this issue:

1. Sign in to Webex Site Administration and go to Configuration > Common Site settings > Options.
2. In the Cloud Collaboration Meeting Rooms Options section, check the Enable Video call-back check box.
3. Choose whether users must press 1 to join meetings or events:
   • without pressing "1"
   • must press "1"

     Note: Users on the Webex Meetings application version 39.8 and later can choose to connect their video system with or without pressing 1 themselves under Preferences > Video system > Call my video system.

4. Select Update.