I get a System.NullReferenceException when I attempt the challenge. It works when I copy the code over to the workspace?

using System;

namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {


            while (true)
            {
                Console.Write("Enter the number of times to print \"Yay!\": ");
                var times = Console.ReadLine();
                    if (times.ToLower() == "quit")
                    {
                    Console.WriteLine("Goodbye!");
                    break;
                    }
                try
                {
                int loopRuns = int.Parse(times);

                        if (loopRuns <= 0)
                        {
                         Console.WriteLine("You entered an invalid number");
                         continue;
                        }
                        else
                        {



                            while(true)
                            {
                                if (loopRuns <= 0)
                                {
                                break;
                                }
                                else
                                {
                                Console.WriteLine("Yay!");
                                }
                                loopRuns = loopRuns - 1 ;
                            }
                        }
                 }
                 catch(FormatException)
                 {
                   Console.WriteLine("That is not valid input.");
                   continue;
                 }



            } 
        }
    }
}