how to run multiple .NET core web hosts in IIS?

Currently am developing a web application using .net core. To support multiple tenants, I have created multiple web hosts in program.cs like below

public class Program
{
    public static async Task Main(string[] args)
    {
        var host = CreateHostBuilder(args).Build();
        var mthost = CreateHostBuilderTest(args).Build();

        await Task.WhenAny(host.RunAsync(), mthost.RunAsync());
    }

    public static IHostBuilder CreateHostBuilder(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureWebHostDefaults(webBuilder =>
            {                    
                webBuilder.UseStartup<DefaultTenantStartup>();
                webBuilder.UseUrls("http://localhost:50001", "https://localhost:50002");
                webBuilder.PreferHostingUrls(true);
            });

    public static IHostBuilder CreateHostBuilderTest(string[] args) =>
        Host.CreateDefaultBuilder(args)
            .ConfigureWebHostDefaults(webBuilder =>
            {                    
                webBuilder.UseStartup<SecondTenantStartup>();
                webBuilder.UseUrls("http://localhost:50101", "https://localhost:50102");
                webBuilder.PreferHostingUrls(true);
            });
}

The issue is that the above code works perfectly with kestrel and dotnet command line execution. However, when I host the application in IIS I don't see both the hosts running in parallel. Rather the second one always handles the requests.

Any one tried such things previously?