Program ends after user input is invalid

Try this code

    static void Main(string[] args)
    {
        string First;
        string Last;
        First = "Cristiano";
        Last = " Ronaldo";
        Console.Write("Please enter student name <First Last>: ");
        Console.WriteLine(First + Last);

        Console.WriteLine(" ");

        Console.WriteLine("*************NOTE**********************************************");
        Console.WriteLine("*** Be sure to include decimal point for scores.            ***");
        Console.WriteLine("***     !!!All score should range from 0.00 to 100.00 !!    ***");
        Console.WriteLine("***                                                         ***");
        Console.WriteLine("*** For example : 80.50                                     ***");
        Console.WriteLine("***************************************************************");

        Console.WriteLine(" ");

        double Exam_1 = -1;
        double Exam_2;
        double Exam_3;
        double Assignment_1;
        double Assignment_2;

        Console.Write("Please enter score for Exam 1 <Example: 100.0>: ");
        Exam_1 = Convert.ToDouble(Console.ReadLine());
        var exitProgram = false;
        var errorCount = 0;

        while (Exam_1 < 0.0 || Exam_1 > 100.0)
        {
            Console.Write("Exam score cannot be less than 0. or greater than 100.0. Please re-enter the score for Exam 1 <Example: 95.0>:");
            Exam_1 = Convert.ToDouble(Console.ReadLine());
            ++errorCount;
            ErrorCount(errorCount);
        }

        Console.Write("Please enter score for Exam 2 <Example: 0.0>: ");
        Exam_2 = Convert.ToDouble(Console.ReadLine());
        errorCount = 0;
        while (Exam_2 < 0.0 || Exam_2 > 100.0)
        {
            Console.Write("Exam score cannot be less than 0.0 or greater than 100.0. Please re-enter the score for Exam 2 <Example: 95.0>:");
            Exam_2 = Convert.ToDouble(Console.ReadLine());
            ++errorCount;
            ErrorCount(errorCount);
        }

        Console.Write("Please enter score for Exam 3 <Example: 60.8>: ");
        Exam_3 = Convert.ToDouble(Console.ReadLine());
        errorCount = 0;
        while (Exam_3 < 0.0 || Exam_3 > 100.0)
        {
            Console.Write("Exam score cannot be less than 0.0 or greater than 100.0. Please re-enter the score for Exam 3 <Example: 95.0>:");
            Exam_3 = Convert.ToDouble(Console.ReadLine());
            ++errorCount;
            ErrorCount(errorCount);
        }

        Console.WriteLine(" ");

        Console.Write("Please enter score for Assignment 1 <Example: 100.0>: ");
        Assignment_1 = Convert.ToDouble(Console.ReadLine());
        errorCount = 0;
        while (Assignment_1 < 0.0 || Exam_2 > 100.0)
        {
            Console.Write("Assignment score cannot be less than 0.0 or greater than 100.0. Please re-enter the score for Assignment 1 <Example: 95.0>:");
            Assignment_1 = Convert.ToDouble(Console.ReadLine());
            ++errorCount;
            ErrorCount(errorCount);
        }

        Console.Write("Please enter score for Assignment 2 <Example: 23.46>: ");
        Assignment_2 = Convert.ToDouble(Console.ReadLine());
        errorCount = 0;
        while (Assignment_2 < 0.0 || Assignment_2 > 100.0)
        {
            Console.Write("Assignment score can not be less than 0.0 or greater than 100.0. Please re-enter the score for Assignment 2 <Example: 56.0>: ");
            Assignment_2 = Convert.ToDouble(Console.ReadLine());
            ++errorCount;
            ErrorCount(errorCount);
        }

        Console.WriteLine(" ");

        Console.WriteLine(" -------------- OUTPUT ---------------");

        Console.WriteLine(" ");

        Console.Write("Student: ");
        Console.WriteLine(First + Last);

        Console.WriteLine(" ");
        Console.Write("Press any key to continue . . . ");
        Console.ReadLine();
    }

    public static void ErrorCount(int errorCount)
    {
        if (errorCount > 0)
        {
            Console.Write("Error count too much ! . . . ");
            Console.Write("Press any key to exit . . . ");
            Console.ReadKey();
            Environment.Exit(0);
        }

    }

Bear in mind it doesn't detect if the user enters an alpha numeric number or special characters but you get the idea.