When I arranged assistant forwarding call to a SIP URI it was forwarded. But never arrived to my SIP server. No even hits in logs of the SIP credentials. Can you suggest what should I take a look in to?

Hi Vladimir, To troubleshoot why your forwarded call didn't arrive at your SIP server, you can follow these steps: 1. **Verify Call Ended Reason**: Check if the ended reason for the call is recorded as

assistant-forwarded-call

. Use the Vapi API to get the call details:

bash
   curl -X GET "https://api.vapi.ai/call/{call_id}" \
   -H "Authorization: Bearer YOUR_API_KEY" \
   -H "Content-Type: application/json"

2. **Check SIP Configuration**: Ensure that your SIP endpoint is correctly configured in Vapi, and that the SIP credentials are accurate. 3. **Analyze SIP Packets**: If using SIP trunking, download and analyze the SIP packet capture using Wireshark to check for the presence of

REFER

packets:

bash
   curl -X GET "https://api.vapi.ai/call/{call_id}" \
   -H "Authorization: Bearer YOUR_API_KEY"

Filter using Wireshark:

sip.Method == "REFER"

. 4. **Server Message Configuration**: Confirm if any server messages might be overriding the assistant's call control. Remove

"phone-call-control"

unless required. 5. **SIP Provider Logs**: Look into your SIP provider's logs to see if any errors or rejected connections are recorded. 6. **Configuration Check**: Ensure the

phoneCallProviderBypassEnabled

is set correctly, as it affects call control. Refer to the [Vapi debug forwarding drops](https://docs.vapi.ai/phone-calling/transfer-calls/debug-forwarding-drops) documentation for a more detailed guide on resolving the issue. These steps should help identify where the process is failing. If the forwarded call is showing as successful but not arriving, the issue might be with the configuration or compatibility with the SIP provider.