Phone number on my Coversaional Flow Agent doesnt work

Support Help
1

I have connected a Twillio number with SIP and hen I connect the number with any agent , I call and everything is fine. But when I put my Covesational Flow Agent with the same phone number, I call , it rings but it doesnt pick up

2

When your Twilio number connected via SIP trunk works with some agents but not with your Conversational Flow Agent (the call rings but doesn’t pick up), this indicates an agent-specific configuration issue rather than a telephony setup problem(1).

Based on similar cases, when a particular agent isn’t picking up calls while the same number works with other agents, the issue is typically with the agent configuration itself(1). One user reported that when they assigned a non-working number to another agent, it worked fine, confirming the problem was agent-specific(1).

Steps to troubleshoot:

  1. Verify your SIP trunk configuration - Ensure your origination setting in Twilio points to Retell’s SIP server: sip:sip.retellai.com(2). Check your Twilio logs for any errors(2).

  2. Check agent binding - Confirm the Conversational Flow Agent is properly bound to the imported number(2). You can verify this in your Retell dashboard under the phone number settings.

  3. Review agent settings - Check if there are any specific configurations in your Conversational Flow Agent that might prevent it from answering calls (such as disabled states, incorrect prompts, or missing required tools).

  4. Test with a duplicate - Try duplicating your Conversational Flow Agent to see if the issue persists with the copy(1).

If the problem continues after checking these items, you may want to:

3

Hello @Thanassis_Psixramis
Can you share a call id?

5

I dont have a call id the call doesnt even start

6

I have tried all 4 again. everything seems fine but again does not work

7

Hello @Thanassis_Psixramis

Can you share the Agent id, and the call doesn’t even show up on the call history?

8

agent_c3e37f43134a33b0caf58fd1b1

9

I understand you’ve provided an agent ID: agent_c3e37f43134a33b0caf58fd1b1.

If you’re experiencing issues retrieving this agent via the API, the correct endpoint to use is:

https://api.retellai.com/v1/get-agent/{agent_id}

(1)

Make sure you’re using /get-agent/ in the URL path rather than /agent/(1), and replace {agent_id} with your actual agent ID: agent_c3e37f43134a33b0caf58fd1b1(1).

Your request should look like:

curl -X GET "https://api.retellai.com/v1/get-agent/agent_c3e37f43134a33b0caf58fd1b1" -H "Authorization: Bearer YOUR_API_KEY"

If you need to update this chat agent, you can use the update endpoint documented in the API references(2).

10

Yeah it doesn’t show up. I call it rings for a 5 seconds and then it hangs up itself. When I go to call history there is nothing there

11

The interesting part is that it works if I put the number to another agent. So I am really wondering if it’s something wrong with the way I built the agent or just a weird bug

12

Based on similar cases, there are a few things to verify when the transfer number works with one agent but not another:

Check the transfer_option field

When configuring the transfer_call tool in your LLM, ensure you’re including the transfer_option field(1). A user experienced a similar issue where the transfer destination showed the wrong number, and it was resolved by adding this required field(1).

Your transfer_call configuration should look like this:

{
    "type": "transfer_call",
    "name": "transfer_to_maddie",
    "description": "Transfer the call to Maddie, our consultant.",
    "transfer_destination": {
        "type": "predefined",
        "number": "+13473770030"
    }
}

(1)

Verify agent-phone number assignment

Double-check that your phone number is assigned exclusively to the specific agent ID you’re testing(2). Even if you’ve verified this before, re-confirm the assignment since agent switching can occur if multiple agents are somehow linked to the same number(2).

SDK version

Make sure you’re using the latest SDK version, as older versions may have had issues with required fields not being properly validated(1).

If the issue persists after verifying these points, you can reach out for support:

13

Hello, this issue happens because an error happened with your inbound webhook. Please try disabling the inbound webhook and then attempt the call again it should work afterward.

14

Okay yeah it seems that it works if I remove it. But that webhook is key to my solution. Also it was working with other agents.

15

I got it . Thanks a lot. No more questions.