Авторизация на web портале из c# приложения

Первый запрос проходит, а второй нет. Что я упускаю???

    class Program
    {
        static void Main(string[] args)
        {
           
 
            var user = "user";
            var password = "password";
            var cookies = new CookieContainer();
            var proxy = new WebProxy("127.0.0.1:8888");




            var getRequest = new GetRequest()
            {
                Address = "https://wsdemo.laximo.ru/",
                AcceptLanguage = "en-US,en;q=0.7,ru;q=0.3",
                Accept = "text/html, application/xhtml+xml, image/jxr, */*",
                Host = "wsdemo.laximo.ru",
                KeepAlive = true,
                TurnOffProxy = true

            };

        
            var data = $"{{\"user%5Blogin%5D={WebUtility.UrlEncode(user)}&user%5Bpassword%5D={WebUtility.UrlEncode(password)}&user%5Bbackurl%5D=https%3A%2F%2Fwsdemo.laximo.ru%2Findex.php%3Ftask%3Dcatalogs\"}}";


            var postRequest = new PostRequest()
            {
                Data = data,
                Address = $"https://wsdemo.laximo.ru/index.php?task=login&view=login",
                Accept = "text/html, application/xhtml+xml, image/jxr, */*",
                Host = "wsdemo.laximo.ru",
                ContentType = "text/html; charset=UTF-8",
                Referer = "https://wsdemo.laximo.ru/index.php?task=catalogs",
                
                KeepAlive = true,
                Proxy = proxy
            };
            postRequest.AddHeader("Origin", "https://wsdemo.laximo.ru");



            postRequest.Run(ref cookies);


            getRequest = new GetRequest()
            {
                Address = $"https://wsdemo.laximo.ru/index.php?task=catalogs&auth=true",
                AcceptLanguage = "en-US,en;q=0.7,ru;q=0.3",
                Accept = "text/html, application/xhtml+xml, image/jxr, */*",
                Host = "wsdemo.laximo.ru",
                ContentType = "text/html; charset=UTF-8",
                KeepAlive = true,
                Referer = "https://wsdemo.laximo.ru/index.php?task=catalogs",
                Proxy = proxy

            };


            getRequest = new GetRequest()
            {
                Address = $"https://wsdemo.laximo.ru/index.php?task=catalogs&auth=true",
                Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9",
                Host = "wsdemo.laximo.ru",
                ContentType = "text/html; charset=UTF-8",
                KeepAlive = true,
                Referer = "https://wsdemo.laximo.ru/index.php?task=catalogs",
                Proxy = proxy
            };
            getRequest.Run(ref cookies);



         //   Config.Instance.AddLogInfo(getRequest.Response);
        }
    }
}

[![введите сюда описание изображения][1]][1]


  [1]: https://i.stack.imgur.com/VGFRX.png