Whenever I try to create a call out using Vapi API, I get this error: { "message": [ "customers.0.number must be a valid phone number in the E.164 format. Hot tip, you may be missing the country code (Eg. US: +1)." ], "error": "Bad Request", "statusCode": 400 } The phone number is in the correct format.

Try this example payload to ensure your phone number is in the correct E.164 format and the structure matches Vapi's requirements:

json
{
  "customers": [
    {
      "number": "+12345678900"
    }
  ],
  "assistantId": "your-assistant-id",
  "phoneNumberId": "your-phone-id"
}

Make sure there are no spaces, the "+" is present, and the country code is correct. Even a small typo or extra character can cause this error. [See Vapi API docs for details](https://docs.vapi.ai/api-reference/calls/create) Sources: - [Vapi API Reference: Create Call](https://docs.vapi.ai/api-reference/calls/create) - [Vapi Dynamic Variables Guide](https://docs.vapi.ai/assistants/dynamic-variables#prepare-your-request)

i did confirm this but still not working

Hey, can you share the call request? By the way, our customer property is not of type array, it's of type record. So you have to pass them as in JSON and set the number E164 check property to false to make it work.

here is the call request: { "assistantId": "85747a5d-3111-4e00-8d27-3b380281772c", "phoneNumberId": "{{$json.phoneNumberId}},", "customer": { "name": "{{ $json.name }}", "number": "{{ $json.phone }}" } } going from n8n to vapi to make the call https://cdn.discordapp.com/attachments/1374810524130480168/1375084009071050813/image.png?ex=68306647&is=682f14c7&hm=5b5a940c893fe2fb97d9eff47503447a9a989b914f33aa964e73b7a58a229270& https://cdn.discordapp.com/attachments/1374810524130480168/1375084009406857216/image.png?ex=68306647&is=682f14c7&hm=2ecdf3588d2c65a810436554deb4969d4bbd13a04b12382e4be16ac9b5177b04&

Here's the solution: curl -X POST \\ \-H "Authorization: Bearer YOUR_API_KEY" \\ \-H "Content-Type: application/json" \\ \-d '{ "customers": \[{ "name": "YOUR_CUSTOMER_NAME", "number": "YOUR_PHONE_NUMBER", "numberE164CheckEnabled": false }\], "assistantId": "YOUR_ASSISTANT_ID", "phoneNumberId": "YOUR_PHONE_NUMBER_ID" }' \### What to replace: \- `YOUR_API_KEY`: Your Vapi API key \- `YOUR_CUSTOMER_NAME`: Customer name (e.g., "Test Call") \- `YOUR_PHONE_NUMBER`: The phone number that was failing validation \- `YOUR_ASSISTANT_ID`: Your Vapi assistant ID \- `YOUR_PHONE_NUMBER_ID`: Your Vapi phone number ID \### What I fixed: I added the

numberE164CheckEnabled: false

parameter to the customer object, which disables the strict E.164 validation while still ensuring basic validation rules. This will allow your call to go through even if your phone number doesn't strictly conform to E.164 format or uses test numbers.

it doesn't work. even when doing a test in the api reference page of docs.vapi.ai, i get a response of: { "message": "Failed to create calls for the following customers: +13155294769", "error": "Bad Request", "statusCode": 400 } for any phone number i try to use & assistantId & phonenumberId

Try this corrected payload structure for your API call:

json
{
  "customers": [
    {
      "name": "Test Call",
      "number": "+13155294769",
      "numberE164CheckEnabled": false
    }
  ],
  "assistantId": "YOUR_ASSISTANT_ID",
  "phoneNumberId": "YOUR_PHONE_NUMBER_ID"
}

Make sure you use the

customers

array (not

customer

), and include

numberE164CheckEnabled: false

if you're testing with non-standard numbers. Double-check that your assistant and phone number IDs are valid and active in your Vapi dashboard. [See Vapi API Reference: Create Call](https://docs.vapi.ai/api-reference/calls/create) Source: - [Vapi API Reference: Create Call](https://docs.vapi.ai/api-reference/calls/create)

Hey, sorry to hear about the issue with your account. Could you please record a loom video showing the error or behavior you're experiencing? It would really help us understand the problem better.

here is the recording: https://somup.com/cThvbtMPI2

Yes, it does. Just remove the num164 check and the name property from the API request and it will work properly.

still getting the same error: { "message": "Failed to create calls for the following customers: +13155294769", "error": "Bad Request", "statusCode": 400 }

curl -X POST https://api.vapi.ai/call \
  -H "Authorization: Bearer xxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "customer": {
      "number": "+13155294769",
       "numberE164CheckEnabled": false
    },
    "assistantId": "85747a5d-3111-4e00-8d27-3b380281772c",
    "phoneNumberId": "1228c413-da84-4752-984a-b4613c2e8c57"
  }'

Try this curl request and let me know how it goes for you.

ok that worked but now im getting this: { "errorMessage": "Bad request - please check your parameters [item 14]", "errorDescription": "Bad Request", "errorDetails": { "rawErrorMessage": [ "400 - \"{\\\"message\\\":\\\"Over Concurrency Limit.\\\",\\\"error\\\":\\\"Bad Request\\\",\\\"statusCode\\\":400}\"" ], "httpCode": "400" }, "n8nDetails": { "nodeName": "HTTP Request", "nodeType": "n8n-nodes-base.httpRequest", "nodeVersion": 4.2, "itemIndex": 14, "time": "6/6/2025, 2:11:45 PM", "n8nVersion": "1.84.3 (Cloud)", "binaryDataMode": "filesystem", "stackTrace": [ "NodeApiError: Bad request - please check your parameters", " at ExecuteContext.execute (/usr/local/lib/node_modules/n8n/node_modules/n8n-nodes-base/dist/nodes/HttpRequest/V3/HttpRequestV3.node.js:525:33)", " at processTicksAndRejections (node:internal/process/task_queues:95:5)", " at WorkflowExecute.runNode (/usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:681:27)", " at /usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:913:51", " at /usr/local/lib/node_modules/n8n/node_modules/n8n-core/dist/execution-engine/workflow-execute.js:1246:20" ] } }

Hey, can you share the org_id? You can find it [here](https://dashboard.vapi.ai/org/settings). This will help me get more details about it.