.NET Core Web Api Error -4090 EADDRNOTAVAIL address not available on Azure

I have a .NET Core 1.1 Web Api project that works great locally. Once I deploy it to AppService on Azure, it will not respond to any GET requests - they all time out. I have an open ping endpoint that simply returns current date and time and it is not responding. Looking at the logs I see this:

[INF] Azure Web Sites environment detected. Using '"D:\home\ASP.NET\DataProtection-Keys"' as key repository; keys will not be encrypted at rest. (383ad3af)
[WRN] Unable to bind to http://localhost:22676 on the IPv6 loopback interface. (de7f78a0)
System.AggregateException: One or more errors occurred. (Error -4090 EADDRNOTAVAIL address not available) ---> Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvException: Error -4090 EADDRNOTAVAIL address not available
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.tcp_bind(UvTcpHandle handle, SockAddr& addr, Int32 flags)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvTcpHandle.Bind(ServerAddress address)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.TcpListener.CreateListenSocket()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Listener.<StartAsync>b__8_0(Object state)
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.ThrowIfExceptional(Boolean includeTaskCanceledExceptions)
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.Tasks.Task.Wait()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.KestrelEngine.CreateServer(ServerAddress address)
   at Microsoft.AspNetCore.Server.Kestrel.KestrelServer.Start[TContext](IHttpApplication`1 application)
---> (Inner Exception #0) Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvException: Error -4090 EADDRNOTAVAIL address not available
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.Libuv.tcp_bind(UvTcpHandle handle, SockAddr& addr, Int32 flags)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Networking.UvTcpHandle.Bind(ServerAddress address)
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.TcpListener.CreateListenSocket()
   at Microsoft.AspNetCore.Server.Kestrel.Internal.Http.Listener.<StartAsync>b__8_0(Object state)<---

I am not sure why this is happening and how to resolve it.

EDIT: Here is the Program.cs

public static void Main(string[] args)
    {
        var configuration = new ConfigurationBuilder()
            .AddEnvironmentVariables()
            .AddCommandLine(args)
            .Build();

        var host = new WebHostBuilder()
            .ConfigureLogging(options => options.AddConsole())
            .ConfigureLogging(options => options.AddDebug())
            .UseConfiguration(configuration)
            .UseIISIntegration()
            .UseKestrel(options =>
            {
                options.ThreadCount = 1;
            })
            .UseStartup<Startup>()
            .Build();

        host.Run();
    }