NotificationUpdate(NotificationUpdate)

{
    "title": "string",
    "content": "string",
    "summary": "string",
    "priority": "low",
    "status": "pending",
    "scheduled_at": "2019-08-24T14:15:22.123Z",
    "expires_at": "2019-08-24T14:15:22.123Z"
}