Hi VAPI Support Team, I'm trying to implement a flow where if the specialist is busy or doesn't answer, the call returns to the agent. I understand that VAPI currently does not support this natively, so I tested the "on-hold specialist" feature to achieve a similar experience. In this setup, the agent successfully dials the specialist, and the caller and specialist join the conference. However, the agent never joins the conference at all, making it impossible to maintain the agent in the call or return the conversation to them if the specialist is unavailable. According to Twilio's documentation, the agent's call should also be initiated in conference mode in order to allow this. Could you confirm if this is a limitation of the current VAPI flow or if there's a recommended workaround to achieve this fallback-to-agent behavior?

**This is a current limitation of the Vapi "on-hold specialist" flow**—the agent is not automatically joined to the conference, so fallback-to-agent is not natively supported. The recommended workaround is to add the agent as a participant to the Twilio conference from the start, so if the specialist is unavailable, the agent remains in the call and can resume the conversation. Update your conference logic to include the agent, caller, and specialist as participants, and use Twilio's status callbacks to handle no-answer events and return control to the agent as needed. For more details, see the [Vapi Call Handling with Twilio documentation](https://docs.vapi.ai/calls/call-handling-with-vapi-and-twilio). Source: - [Vapi Call Handling with Twilio](https://docs.vapi.ai/calls/call-handling-with-vapi-and-twilio)

Hey Mubashshir Ansari, I want to clarify that this documentation only establishes a connection between the customer and the specialist. The agent is supposed to take a leave from the call in case you want to add the assistant because the specialist doesn't answer the call. You can tweak the code according to your requirements. Let me know if you require any help with this. Also, we have another transfer mode called "warm transfer" (experimental) which does a similar thing. You can check out the same in our documentation. For your information, this feature only works for Twilio-based coils.