C# – cannot convert from threading task to system action

i have problem to run task in button
Problem is : cannot convert from threading.task.task to system action
i marked the line in the button

         private async void BtnStart_Click(object sender, EventArgs e)
         {


        if (String.IsNullOrEmpty( txtProxy.Text) || lstviewcomp.Items.Count==0)
        {
            MessageBox.Show("Please uploads files");
            return;
        }
        proxies = txtProxy.Text.Split('\n');
        proxycount = proxies.Length;
        foreach (string item in lstviewcomp.Items)
        {
            proxycount++;
            if (proxyCounter> proxycount)
            {
                proxyCounter = 0;
            }
            ProxyInfo = proxies[proxyCounter].Split(',');
            var result = await Task.Run( MainAsync("", "", "", "", "", "")).GetAwaiter().GetResult();// Problem in this line 


            // proxyCounter++;
        }
    }

public async Task MainAsync(string instausername,string pass,string proxyip,string proxyport,string proxyusername,string proxypass)

        {

            try

            {

                // create user session data and provide login details

                var userSession = new UserSessionData

                {

                    UserName = instausername,

                    Password = pass

                };

                // create proxy handeler

                var httpHndler = new HttpClientHandler();

                IWebProxy proxy = new WebProxy(proxyip,Convert.ToInt32(proxyport));

                proxy.Credentials = new NetworkCredential(proxyusername, proxypass);

                httpHndler.Proxy = proxy;

                // create new InstaApi instance using Builder

                _instaApi = new InstaApiBuilder()

                    .SetUser(userSession)

                    .UseHttpClientHandler(httpHndler)

                    .UseLogger(logger: new DebugFileLogger()) // use logger for requests and debug messages

                    .SetRequestDelay(TimeSpan.FromSeconds(1)) // set delay between requests

                    .Build();
            // login

            txtLog.Text = txtLog.Text + $"Logging in as {userSession.UserName}"+" At "+DateTime.Now+"\n";

            var logInResult = await _instaApi.LoginAsync();

            if (!logInResult.Succeeded)

            {

                txtLog.Text = txtLog.Text + $"Unable to login: {logInResult.Info.Message}" + " At " + DateTime.Now + "\n";

            }

            else

            {

                txtLog.Text = txtLog.Text + $"Logging in success : {userSession.UserName}" + " At " + DateTime.Now + "\n";
            }

        }

        catch (Exception ex)

        {

            Console.WriteLine(ex);

        }

        finally

        {

            var logoutResult = Task.Run(() => _instaApi.LogoutAsync()).GetAwaiter().GetResult();

            if (logoutResult.Succeeded) txtLog.Text = txtLog.Text + "Logout sucess \n";
        }

        return false;

    }