while loop with a boolean variable in an int method

I have written two methods and added an infinite while loop in the method.

• The first method

    public static int GetNumber()
        {
            bool isCountinue = true;
            while (isCountinue)
            {
                Console.Write("Please enter an integer number: ");
                string value = Console.ReadLine();
                bool isInteger = int.TryParse(value, out int number);
                if (isInteger)
                {
                    return number;
                }
                else
                {
                    Console.WriteLine("Your input is not an integer number!");
                    isCountinue = false;
                }
            }
        }

• The second method

public static int GetNumber()
    {
        while (true)
        {
            Console.Write("Please enter an integer number: ");
            string value = Console.ReadLine();
            bool isInteger = int.TryParse(value, out int number);
            if (isInteger)
            {
                return number;
            }
            else
            {
                Console.WriteLine("Your input is not an integer number!");
                continue;
            }
        }
    }

I have gotten an error for the first method. Because it is missing the return value in the first method. I am confused why the second method is correct, and the first method is wrong?