DUPLICATE_IDENTITY Cancel Outbound Call

[BisarOmer]

Hello, i am implementing outbound call, DUPLICATE_IDENTITY make livekit send cancel, it would immediately disconnect the sip connection.

my question is, it is a good way to handle DUPLICATE_IDENTITY in an outbound call? i think the call should be continue and do not let the second user join, not terminating the call.

sip	v2@v2.2.2-0.20241015094126-b8538ae5d67b/engine.go:666	server initiated leave	{"nodeID": "NE_MrRr4bJymkQF", "sipTrunk": "ST_i8ncqYBaz3ry", "callID": "SCL_jzRVSBwJuacs", "room": "outbound-call", "participant": "", "participantName": "", "fromHost": "", "fromUser": "", "toHost": "", "toUser": "", "reason": "DUPLICATE_IDENTITY", "canReconnect": false}

sip	sip/outbound.go:392	SIP invite failed	{"nodeID": "NE_MrRr4bJymkQF", "sipTrunk": "ST_i8ncqYBaz3ry", "callID": "SCL_jzRVSBwJuacs", "room": "outbound-call", "participant": "", "participantName": "", "fromHost": "", "fromUser": "", "toHost": "", "toUser": "", "error": "canceled"}

sip      | 2025-07-30T10:44:56.576Z	WARN	sip	sip/outbound.go:174	Closing outbound call with error	{"nodeID": "NE_MrRr4bJymkQF", "sipTrunk": "ST_i8ncqYBaz3ry", "callID": "SCL_jzRVSBwJuacs", "room": "outbound-call", "participant": "", "participantName": "", "fromHost": "", "fromUser": "", "toHost": "", "toUser": "", "reason": "invite-failed"}

sip      | 2025-07-30T10:44:56.576Z	INFO	sip	sip/outbound.go:129	SIP call failed	{"nodeID": "NE_MrRr4bJymkQF", "sipTrunk": "ST_i8ncqYBaz3ry", "callID": "SCL_jzRVSBwJuacs", "room": "outbound-call", "participant": "", "participantName": "", "fromHost": "", "fromUser": "", "toHost": "", "toUser": "", "error": "update SIP failed: canceled"}

[biglittlebigben]

Can you speak more about your use case and call flow? In pretty much all use cases so far, the new participant pushing out the old one is the expected behavior

[BisarOmer]

Note: Closing this issue was accident

User from the app initiates an outbound call. After setting up the trunk via CreateSIPOutboundTrunk:

	sipParticipant := SIPParticipant{
		TrunkID:             trunk.ID(),
		PhoneNumber:         CallTo,
		RoomName:            Phone,
		ParticipantIdentity: Phone,
	}

	CreateSIPParticipant(sipParticipant)

I call CreateSIPParticipant to trigger the call. This automatically adds a participant to the room using the RoomName and ParticipantIdentity I provide. Then I generate a new access token via NewAccessToken for my user to join the room with the same identity. This causes a DUPLICATE_IDENTITY error, and LiveKit SIP sends a cancel to the SIP trunk provider.

The solution right now is providing a different identity for CreateSIPParticipant, The room then ends up with three participants—one of them is the unused one created by CreateSIPParticipant.

[nishadmusthafa]

You cannot have 2 participants with the same identity in a room. What exactly is your goal with using createsipparticipant and then another operation with the NewAccessToken ? Are you trying to have one person from web app connect to someone on PSTN/SIP ?

[BisarOmer]

Livekit SDK does not provide a func to initiate Outbound call without automatically join a user to the room, therefore i use CreateSIPParticipant to initiate the call. then get access token for the user.

yes i use livekit sip to make connection between a user from Web or OTT Mobile Communication application to make call for a phone number

[nishadmusthafa]

I see. To clarify, do you want the web user to automatically join the room or not automatically join the room ? Could you also share what API in the SDK you tried to use ?

[BisarOmer]

in the sipclient.go livekit SDK the only func which start the outbound call is // CreateSIPParticipant creates SIP Participant by making an outbound call. with this parameter *livekit.CreateSIPParticipantRequest

	request := &livekit.CreateSIPParticipantRequest{
		SipTrunkId:          sipParticipant.TrunkID,
		SipCallTo:           sipParticipant.PhoneNumber,
		RoomName:            sipParticipant.RoomName,
		ParticipantIdentity: sipParticipant.ParticipantIdentity,
		ParticipantName:     sipParticipant.ParticipantName,
		PlayDialtone:        true,
	}

the issue is that both ParticipantIdentity and ParticipantName is required and Livekit automatically add that participant to the room, then my user should join the room from the client application to speak with the callee which is on PSTN it will cause DUPLICATE_IDENTITY.

Livekit should provide a fun to make outbound call without requiring a default participant to the room.

[nishadmusthafa]

So the PSTN user and the participant on the web client are two different participants. Why would you want to give them the same identity ?

[BisarOmer]

then my user should join the room from the client application to speak with the callee which is on PSTN

No, they are two different user one from my app the other is a telecom carrier user.

[nishadmusthafa]

Then I generate a new access token via NewAccessToken for my user to join the room with the same identity.

Could you share the code for this ?

[BisarOmer]

at := auth.NewAccessToken(s.Engine.Envs[core.LiveKitAPIKey], s.Engine.Envs[core.LiveKitAPISecret])
	grant := &auth.VideoGrant{
		RoomJoin: roomJoin,
		Room:     room,
	}
	at.SetVideoGrant(grant).
		SetIdentity(identity).
		SetValidFor(duration).
		SetName(name)

the problem is Sending CANCEL in the sip connection, when DUPLICATE_IDENTITY occur.