Kindly make sure that the Advanced Mode is enabled by going to Configurations and enabling the Advanced Mode found below.
To enable the ticket's voice calling/announcement please follow the steps below.
Go to Services in the portal and click on Queues.
2. Choose a queue and click on edit.
3. Go to Screen Options under Settings and enable the Announcer for the calling and Sound for the beeping.
4. Scroll down to the bottom of the page and click on Save.