WABP: incoming webhook status

[nbartels]

{
  "object": "whatsapp_business_account",
  "entry": [
    {
      "id": "101809759215303",
      "changes": [
        {
          "value": {
            "messaging_product": "whatsapp",
            "metadata": {
              "display_phone_number": "1234567891",
              "phone_number_id": "10634295353625"
            },
            "statuses": [{
              "id": "wamid.ID",
              "recipient_id": "PHONE_NUMBER",
              "status": "sent",
              "timestamp": "TIMESTAMP",
              "conversation": {
                "id": "CONVERSATION_ID",
                "expiration_timestamp": "TIMESTAMP",
                "origin": {
                  "type": "user_initiated"
                }
              },
              "pricing": {
                "pricing_model": "CBP",
                "billable": true,
                "category": "user_initiated"
              }
            }]
          },
          "field": "messages"
        }
      ]
    }
  ]
}