UnauthorizedAccessException: System access is restrictedNot An Issue

Hola, i have trouble in connection Telegram bot to rust plugin.
Code:

//Reference: Telegram.Bot
using Oxide.Core;
using Oxide.Core.Libraries.Covalence;
using System.Collections.Generic;
using System.IO;
using Oxide.Core.Configuration;
using Telegram.Bot;
using System;

namespace Oxide.Plugins
{
    [Info("Test", "LuL-Z", 1.0)]
    [Description("Testing")]
    public class Program : CovalencePlugin
    {
        [Command("connect", "conn", "cct")]
        private void TestCommand(IPlayer player, string command, string[] args)
        {
			TelegramBotClient bot = new TelegramBotClient("TOKEN");
			bot.SendTextMessageAsync(tg_id_person, "Check Message");
        }
    }
}

Error:

Failed to call hook 'TestCommand' on plugin 'Program v1.0.0' (UnauthorizedAccessException: System access is restricted, you are not allowed to use System.Threading.CancellationToken)
at Oxide.Plugins.Program.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x00032] in <8a3e985d305b41b884ea0fa03e8c523f>:0
at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <9affce1cd15c4ec183941adef8db1722>:0
at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000d8] in <4452f821def6406d834e4149849fe7ea>:0
at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <4452f821def6406d834e4149849fe7ea>:0


How to fix it?


Here is your answer
"System access is restricted, you are not allowed to use System.Threading.CancellationToken"
Yeah, thank you, but i know umod restricted a some namespaces like "System.Threading" is this trouble becouse of that?
Lulz322
Yeah, thank you, but i know umod restricted a some namespaces like "System.Threading" is this trouble becouse of that?

Its restricted, you can't fix it... If you are asking why its blocked -> start thread about it. 

Locked automatically