C# WebRequest - WebResponse to POST a webform with random generated token

Question

I'm trying to login to www.autoscout24.de and retrieve adds and messages. Login form has a random generated hidden input/token. Being new to C#, I've read different tuts about using C# to login to websites and all I found was simple codes that work only in simple login forms (user:pass). I've imagined a 2-step approach: first make a GET request to retrieve needed data and a POST request with login credentials and other needed imputes. Using HtmlAgilityPack I'm passed first step but the second request just returns the login page again instead of "My account" page. My code:

using System;
using System.IO;
using System.Net;
using System.Text;

namespace WebRequest__custom
{
    class Program
    {
        static void Main(string[] args)
        {
            CookieContainer _cookies;
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://angebot.autoscout24.de/login?fromNavi=myAS24");
            WebResponse _response = request.GetResponse();
            Stream stream = _response.GetResponseStream();
            StreamReader strReader = new StreamReader(stream);

            string _cookiesHeader = _response.Headers["Set-cookie"];
            _cookies = request.CookieContainer;
            string _content = strReader.ReadToEnd();
            //Console.WriteLine(_content.Substring(0,500));

            var _dom = new HtmlAgilityPack.HtmlDocument();
            _dom.LoadHtml(_content);

            // Get POST link
            var _postLinkNode = _dom.DocumentNode.SelectSingleNode("//*[@id='loginForm']/div[3]/form");
            var postLink = _postLinkNode.Attributes["action"].Value;
            //Console.WriteLine(postLink);

            //get Token
            var _tokenNode = _dom.DocumentNode.SelectSingleNode("//*[@id='loginForm']/div[3]/form/input");
            var token = _tokenNode.Attributes["value"].Value;
            //Console.WriteLine(token);

            // Start login request
            HttpWebRequest requestLogin = (HttpWebRequest)WebRequest.Create("https://accounts.autoscout24.com"+ postLink);

            requestLogin.ContentType = "application/x-www-form-urlencoded";
            requestLogin.Method = "POST";
            requestLogin.KeepAlive = true;
            requestLogin.AllowAutoRedirect = true;

            string postData = "&__RequestVerificationToken=" + token;
            postData += "&[email protected]";
            postData += "&Password=Qwert123!";
            postData += "&RememberMeCheckBox=on&RememberMe=true";

            byte[] _bytes = Encoding.UTF8.GetBytes(postData);
            requestLogin.ContentLength = _bytes.Length;
            requestLogin.CookieContainer = _cookies;
            using(Stream sr = requestLogin.GetRequestStream())
            {
                sr.Write(_bytes, 0, _bytes.Length);
            }

            WebResponse loginResponse = requestLogin.GetResponse();
            StreamReader loginStreamReader = new StreamReader(loginResponse.GetResponseStream());
            string secondPage = loginStreamReader.ReadToEnd();



            Console.WriteLine(secondPage.Substring(0,500));
            Console.ReadKey();

        }
    }
}