Sip transfer is not working
# supporti
insure0063
07/02/2025, 7:10 PMI can initiate calls to VAPI sip it works , but when it transfers to SIP, the call drops completely.
n
Nir Simionovich (CEO@Cloudonix)
07/02/2025, 9:39 PMDid you setup a proper SIP Trunk with VAPI? Does your SIP trunk support SIP Refer ?
c
Chiranjeet Mishra
07/03/2025, 8:56 PMCould you please provide a call id for the failed transfer call so we can review the logs and PCAP file?
s
Suraj
07/07/2025, 8:51 AMUrgent Support Required: Issues with Vapi Agent Call Transfer and Knowledge Integration
I am facing two critical issues that need immediate attention:
I have created an agent in Vapi that handles initial customer interactions and allows customers to transfer calls to specific departments such as Sales or Service. I have configured multiple department numbers (e.g., Sales: +1-212-122-2200 and Service: +1-245-222-4585). However, the problem is that regardless of whether I instruct the agent to transfer the call to Service, it always redirects the call to the first number in the list (Sales). We have already fine-tuned the prompts and completed all necessary settings, but since we rely on Vapi, we urgently need a solution to resolve this call transfer routing issue.
We have created a Vapi workflow where calls are being successfully transferred; however, the agent is not utilizing the knowledge base we have provided (which is a document spanning 7 pages). This is preventing the agent from responding accurately based on our provided information. Please provide a high-priority resolution for this issue as soon as possible, as it will greatly help us move forward.
Looking forward to your swift response.
c
Chiranjeet Mishra
07/07/2025, 11:44 PMCould you please provide the call id for the call with the failed transfer so we can review the configuration?
s
Suraj
07/08/2025, 6:56 AMcall id : f54803c2-1098-4170-b934-07213306d3a4
c
Chiranjeet Mishra
07/11/2025, 8:53 PM Copy code
{
"callId": "f54803c2-1098-4170-b934-07213306d3a4",
"endedReason": "assistant-forwarded-call",
"callType": "inboundPhoneCall",
"phoneCallTransport": "pstn",
"destinationDetails": {
"type": "number",
"number": "+12xxxx811",
"extension": "7xxx",
"description": "When customer wants to talk to someone from sales department or Steve morell",
"transferPlan": {
"mode": "blind-transfer",
"sipVerb": "refer"
},
"numberE164CheckEnabled": true
},
"phoneCallProviderId": "CAe788182921346f9981d9218b5ac48439",
"phoneCallControlEnabled": false,
"phoneCallProviderBypass": false,
"userGuidance": "PSTN call forwarded successfully. Check telephony provider logs using phoneCallProviderId."
}Chiranjeet Mishra
07/11/2025, 8:59 PMHey, could you please remove the transfer plan and try again? You cannot transfer using a SIP transfer plan from an PSTA number, which is why even after a successful transfer, the call gets dropped. You can verify the same in the Twilio call logs.
3 Views