# PATCH /v1/convai/whatsapp-accounts/{phone_number_id} (ElevenLabs API)
Base URL: https://api.elevenlabs.io
Auth: xi-api-key: <ELEVENLABS_API_KEY>
Last verified: 2026-09-03

> Update Whatsapp Account

## Critical Gotchas
* Authentication uses the non-standard `xi-api-key` header, not `Authorization: Bearer`. Sending a Bearer token returns HTTP 401.
* Text-to-speech responses are raw binary audio, not JSON. Write the body to a file (`--output speech.mp3`) rather than parsing it.

## cURL
curl -X PATCH 'https://api.elevenlabs.io/v1/convai/whatsapp-accounts/phone-number-id' \
  -H "xi-api-key: $ELEVENLABS_API_KEY" \
  -H 'Content-Type: application/json' \
  -d '{"assigned_agent_id":"string","enable_messaging":true}'

## Parameters
| Name | In | Type | Required | Description |
| :--- | :--- | :--- | :--- | :--- |
| phone_number_id | path | string | Yes | path parameter phone_number_id. |
| assigned_agent_id | body | string | No | Request body field assigned_agent_id. |
| enable_messaging | body | boolean | No | Request body field enable_messaging. |
| enable_audio_message_response | body | boolean | No | Request body field enable_audio_message_response. |

## Response (200 OK)
{}

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