curl --request POST \
  --url https://api.v3.tatango.com/transactional_messages/send_whatsapp \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "phoneNumber": "5551234567",
  "webhookUrl": "https://yourpostbackaddress.com",
  "whatsAppTemplateName": "my_template",
  "smsFailover": {
    "content": "Hello world, this is my SMS fallback."
  }
}
'

{
  "message": "Whatsapp template sent successfully",
  "transactionId": "019687e1-1b54-70f4-a68a-60af7fa776f4"
}