Console.ReadLine in async method isn't blocking progression..?

I need to know if there's a way to execute DownloadPage(result) without immediately proceeding to Console.ReadKey() in my main method.

What's happening is that DownloadPage fires, but after displaying "Would you like to save this to a .txt file? [Y/N]", the program ends after typing any key. I originally tried the entire method inside of GetPageHTML, but it keeps breaking as soon as I try to get user input.

I'm still learning C# and I don't know how to approach the problem and correct it. Can anyone help?

using System;
using System.IO;
using System.Net.Http;
using System.Text.RegularExpressions;

namespace Programming_Challenge_4
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.Write("Enter URL: ");
            string url = Console.ReadLine();

            GetPageHTML(url);
            Console.ReadKey();
        }

        static async void GetPageHTML(string _url)
        {
            try
            {
                using (HttpClient client = new HttpClient())
                using (HttpResponseMessage response = await client.GetAsync(_url))
                using (HttpContent content = response.Content)
                {
                    string result = await content.ReadAsStringAsync();
                    string title = Regex.Match(result, @"<title>\s*(.*?)\s*</title>").Groups[1].Value;
                    Console.WriteLine("Downloading HTML...\n\nTitle: {0}\n\n{1}\n\n", title, result);
                    DownloadPage(result);
                }
            }
            catch (Exception)
            {
                Console.WriteLine("There was an error reading the url \"{0}\".", _url);
            }
        }

        static void DownloadPage(string _html)
        {
            Console.WriteLine("Would you like to save this to a .txt file? [Y/N]");
            string saveFile = Console.ReadLine(); // CODE IS BREAKING HERE!

            if (saveFile.ToUpper() == "Y")
            {
                Console.Write("Please provide a file name: ");
                string name = Console.ReadLine();

                using (StreamWriter writer = new StreamWriter(name + ".txt"))
                {
                    writer.Write(_html);
                    writer.Close();
                }

                Console.WriteLine("HTML has been saved to {0}.txt!", name);
            }
        }
    }
}