Hello 👋 I'm using Vonage phone numbers (not Twilio). SCENARIO in 2 steps: 1) Call with id** 0ab8c522-b205-4f60-bcec-a2eee0e355f9** from a customer (number +32 492 85 85 50) to an assistant (Vonage number +32 460 20 83 04 linked to assistant id 51c8b632-0108-4e75-a5a8-0ec185c3af75). This assistant is supposed to transfer the call to another number (Vonage number +32 460 22 50 67, linked to another assistant with id cd37ff71-f729-4466-bec9-77dbe95daeb7), with following transferCall function : "model": { "model": "gpt-4o", "tools": [ { "type": "endCall" }, { "type": "transferCall", "destinations": [ { "type": "number", "number": "+32460225067", "message": "je vous transfère à l'assistante virtuelle personnelle du docteur Riquet", "callerId": "{{customer.number}}", "description": "assistante virtuelle personnelle du docteur Julie Riquet" }, ... } 2) The call is effectively transferred to the number (new call with id fa2512b5-d49f-4f7a-ad34-fe47e34e8ec2), but the call has the {{phoneNumber.number}} as callerId instead of {{customer.number}}. So you will see in the call log of this second call that the customer number is +32 460 20 83 04, which is the Vonage assistant's number that transferred the call, instead of +32 492 85 85 50 which is the customer's number. EXPECTED BEHAVIOUR : I expected to have +32 492 85 85 50 as customer.number. I initially tried to not add the property "callerId" on the transferCall tool destinations, as the documentation says that by default it would give the customer number. However, because I had the phoneNumber.number, I tried to force it by adding the callerId property on each destination, but it still fails to give me the right number.

Based on the information available, there appears to be an issue with Vonage numbers and the callerId parameter. Try purchasing a number directly from Twilio and importing it into Vapi as a potential solution:

json
{
  "type": "transferCall",
  "destinations": [
    {
      "type": "number",
      "number": "+32460225067",
      "callerId": "{{customer.number}}",
      "numberE164CheckEnabled": false
    }
  ]
}

If the issue persists, contact Vapi support with your call IDs for further investigation. Sources: - [Discord Channel](https://discord.com/channels/1211482211119796234/1338285744090906756) - [Discord Channel](https://discord.com/channels/1211482211119796234/1339690911675977838)

By default, we have caller ID feature only for Twilio. If he requires it for Vonage, you’ll have to raise a feature request..

Oh 😓 Added it there : https://vapi.canny.io/feature-requests/p/support-transfercall-tools-callerid-param-for-vonage-numbers

Thanks for sharing, noted.