Ask your provider if they support sending/forwarding caller id from a transfer. They may call it tromboning or some term they use.

You may have to monkey with inband signalling in your external tables.

You could try setting the CNIS number (Class 10.79) for your voicemail ports to the main number

Also, you can tell the ECS not to send CID info to the voicemail system. (VM integration, trunk packet to none) This setting is actually designed for analog POTS trunks, bbut may help you troubleshoot things a bit.

Last edited by JBean3329; 01/07/19 07:17 PM. Reason: more ideas
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