We are trying to understand the following error:

An error occurred in this call: call.start.error-get-transport

which only seems to occur when calling out to US numbers. This is using Twillio provider and there are no logs on their end for this seemingly. Sample Call ID: 019abf62-8bf8-711c-aa30-365ab1305709 Org ID: a266008d-460f-4c11-8a96-1fc935391154 Timestamp: 2025-11-26T08:58:17.976Z

Action Required: The error

call.start.error-get-transport

means Vapi could not retrieve transport information when starting the call. To resolve this, please contact Vapi support and provide your call ID and account details for investigation, as recommended in the [Call ended reasons documentation](https://docs.vapi.ai/calls/call-ended-reason). This is especially important since the issue is specific to US numbers and not immediately clear from your configuration. Source: - [Call ended reasons documentation](https://docs.vapi.ai/calls/call-ended-reason)

same for me. call ID: 019abf92-07fe-700f-8102-d1d6cf59c092

@tf-117 I did find the reason for this, Vapi doesn't do a good job of surfacing the error here, but basically in Twillio specifically for dialing +1 (US) numbers you need to have a verified Customer Profile on Twillio. Ours was pending still and as such the calls are not permitted.

Hi Shmuck, If you're having trouble with outbound calls, please ensure the following: 1. **Account Setup**: You need a Vapi account with a configured assistant and a valid phone number. International calls require an imported number, not a free Vapi number [here](https://docs.vapi.ai/phone-calling). 2. **API Call**: Use the

/call

endpoint for making outbound calls. Make sure to specify a

phoneNumberId

and a

customer

number correctly [here](https://docs.vapi.ai/calls/outbound-calling). 3. **Scheduling Calls**: To schedule, use the

schedulePlan

with the

earliestAt

parameter in ISO date-time format [here](https://docs.vapi.ai/calls/outbound-calling). 4. **Batch Calls**: For multiple calls, provide an array of customers in the API call [here](https://docs.vapi.ai/calls/outbound-calling). 5. **International Calls**: Ensure you're using an imported number since free numbers don't support international calling [here](https://docs.vapi.ai/phone-calling). Check that you have the correct authorization and that your configuration meets these requirements. If the issue persists, verify the configurations in your account and the logs for any error codes to diagnose further.