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If you are searching for hunt groups related to multiple phone line (automatic rollover), you can consult our Dial Plans section for information on configuring multiple trunks to "hunt" or roll-over if the main line is in use for outbound calls. Please see How do I add a new dial plan?
For a "hunt" function on incoming calls, you will need to contact your carrier. The Carrier is responsible for configuring your multiple phone lines to roll-over in whatever configuration you wish. This process takes place before the call reaches your phone system, so Fonality has no control over this roll-over configuration.
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You might assign key press 3 to go to submenu Hunt_Group and in your voice prompt, you would say to the caller, "To reach our marketing department, please press 3".
Read How do I edit keypress options? for instructions on assigning a key press to your Hunt Group.