403 响应 C#, POSTMAN && browser 200, help pls

Question

请帮忙，当用浏览器或邮递员打开链接时，结果是 200 当使用 C# 应用时 - 403

var client = new HttpClient();
var request = new HttpRequestMessage(HttpMethod.get, "https://api2.stepn.com/run/orderlist?order=1002&chain=103&refresh=true&page=0&type=615");

request.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit / 537.11(KHTML, like Gecko) Chrome / 23.0.1271.95 Safari / 537.11"); 
var response = await client.SendAsync(request);

我正在尝试任何标题，但什么都没有