curl --request POST \
  --url https://{operatorDomain}/v1/admin/notifications/preview \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "templateId": "<string>",
  "data": {}
}
'

{
  "subject": "<string>",
  "body": "<string>"
}