Vapi helps developers build, test, and deploy voice agents at scale. We enable everything in between the raw models and production, including telephony, test suites, and real-time analytics.
Build and manage voice AI agents that conduct human-like conversations. Access real-time analytics, configure assistants, and monitor your AI voice applications.
We are sending the SIP REFER request correctly and it seems your telephony provider is not connecting properly. You will need to check with them about it.