transfer call tool does not work 415 - Unsupported...
# supportv
Vladimir
11/05/2025, 7:55 AMassistant id 11c36fb7-8ed2-4d64-a89c-6d033300eb11
call transfer tool id 2ab151b1-d190-41e9-b6ff-4abefd7afd8a
call id 019a52fd-0a4a-7ee2-94ef-383bd1043fda arrives fine from my voice server to ai agent.
when agent asked to transfer call it does it and call returns back to my voice server but always ends with error 415 - Unsupported Media Type or 500 - Server Internal Error Please find pcap files attached and help to resolve it.
https://cdn.discordapp.com/attachments/1435537888992432148/1435537889600471081/call_sipserver_to_vapi.pcap?ex=690c5457&is=690b02d7&hm=d9d93eef7340f2741b1015f5be88642eddff8929aada0a6bedd41433e455a995&
https://cdn.discordapp.com/attachments/1435537888992432148/1435537890217169057/call_vapi_to_sipserver.pcap?ex=690c5458&is=690b02d8&hm=a316f0415c84bf2bea61b1bcfd72a1449f7a85e70bfa0d3762e85450dac857bc&
Vladimir
11/05/2025, 12:45 PMor these 2 calls. Same story with sip 415.
https://cdn.discordapp.com/attachments/1435537888992432148/1435610975926489190/41aa0b18-e61a0a0a-13c4-50017-939b5-16271e51-939b5.pcap?ex=690c9869&is=690b46e9&hm=a6691ee49d17c6648c411d765dc5afdb468062e9d6fd90e9c55c8a87f6362f41&
https://cdn.discordapp.com/attachments/1435537888992432148/1435610976211697664/41aa0cd0-e61a0a0a-13c4-50017-939c8-5709403e-939c8.pcap?ex=690c9869&is=690b46e9&hm=a70747eda58f5c698697b6d77393c26af8f3771215457b781dcb6f99f7f1e391&
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Chiranjeet Mishra
11/07/2025, 7:13 AMHey Vladimir, thanks for sharing your details. Our team will look into it and get back to you soon with an update.