friendlist maintenance

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;

namespace ConsoleApp1
{
    class Exam
    {
        static void Main(string[] args)
        {
            List<string> names = Console.ReadLine().Split(", ").ToList();

            string[] command = Console.ReadLine().Split().ToArray();

            int lostCounter = 0;
            int blackCounter = 0;

            while (command[0] != "Report")
            {
                if (command[0] == "Blacklist")
                {
                    blackCounter = Blacklist(names, command, blackCounter);
                }
                else if (command[0] == "Error")
                {
                    lostCounter = Error(names, command, lostCounter);

                }
                else if (command[0] == "Change")
                {
                    Change(names, command);
                }

                command = Console.ReadLine().Split().ToArray();
            }

            Console.WriteLine($"Blacklisted names: {blackCounter}");
            Console.WriteLine($"Lost names: {lostCounter}");
            Console.WriteLine(string.Join(" ", names));
        }

        private static void Change(List<string> names, string[] command)
        {
            int index = int.Parse(command[1]);

            if (index >= 0 && index < names.Count)
            {
                string nameOld = names[index];
                string newName = command[2];
                names[index] = newName;
                Console.WriteLine($"{nameOld} changed his username to {newName}.");
            }
        }

        private static int Error(List<string> names, string[] command, int lostCounter)
        {
            int index = int.Parse(command[1]);

            if (index >= 0 && index < names.Count)
            {
                if (names[index] != "Blacklisted" && names[index] != "Lost")
                {
                    string name = names[index];
                    names[index] = "Lost";
                    Console.WriteLine($"{name} was lost due to an error.");
                    lostCounter++;
                }
            }

            return lostCounter;
        }

        private static int Blacklist(List<string> names, string[] command, int blackCounter)
        {
            string name = command[1];

            if (names.Contains(command[1]))
            {
                names[names.IndexOf(name)] = "Blacklisted";
                Console.WriteLine($"{name} was blacklisted.");
                blackCounter++;
            }
            else
            {
                Console.WriteLine($"{name} was not found.");
            }

            return blackCounter;
        }
    }
}