I don't know what cause the exception i get

using System;
namespace Treehouse.CodeChallenges
{
    class Program
    {
        static void Main()
        {
          int total = 0;
          int counter = 0;          
          while (true)
          {
            Console.Write("Enter the number of times to print \"Yay!\": ");            
            var user = Console.ReadLine();
            if ( user.ToLower()== "quit")
            { break;}

            // try
            //{
              int numberOfTime = int.Parse(user);            
              while( counter < numberOfTime)
              {
                Console.Write("\"Yay!\": ");
                counter++;
              } 
               counter = 0;
               total += numberOfTime;
              Console.WriteLine("\n"+ "Numbers of Yay enter:"+ total);           
           // }
            //catch (FormatException)
            //{              
             // Console.WriteLine("This is not a number");
             //continue;
            //}   
          }
        }
    }
}