Hello Vapi Support Team, I'm currently experiencing an issue with inbound calls and would appreciate your assistance. Here is the current behavior: The inbound call reaches Vapi successfully. The call is answered by the platform. The audio channel is opened (I can speak normally). However, the call fails immediately after connection. No logs are generated on my side. Based on what I was informed, the call is clearly being accepted by Vapi, which indicates: Inbound is working correctly The number is active The failure happens during routing to the final destination It seems that Vapi answers the call, opens the audio stream, but is unable to route the call properly afterward. For context: I am using a SIP trunk provider. The call connects but fails right after routing should occur. There are no visible error logs in the dashboard. Could you please help me identify: What could cause routing to fail after the call is already accepted? Where I can find detailed routing logs? If there are specific SIP headers or configuration requirements I should verify? If there are known issues related to inbound routing with custom SIP trunks?

Hi @Kelvin Vieira if the call answers and audio opens but drops immediately (with no logs), it usually means the call is accepted but fails during the routing/handshake stage. Please try this step by step: Pull the full SIP trace from your provider (INVITE → 200 OK → ACK → BYE / error). Check the Request-URI / To header matches exactly what Vapi expects. Confirm transport type (UDP vs TCP vs TLS) is correct on both sides. Force codecs to PCMU/PCMA only to avoid negotiation failures. Confirm SIP credentials are updated (username/password) and not cached. Verify the DID is mapped correctly to the assistant (E.164 format like +1xxx). If possible, test using a different DID/provider to isolate the issue. If you share the SIP trace (mask credentials), I can quickly point out the exact failure point.