New Post: Problem publish Tweet

Hi, I'm doing a testing of API with WPF, I try Publish a Tweet but don´t work, with my count:

    private async void PublicMyTweetAsync()
    {
        await Task.Run(() => PublishMyTweet());
    }

    private void PublishMyTweet()
    {
        var newTweet = Tweet.CreateTweet(MyTweet);
        var send = newTweet.Publish();
    }

    private void BtPublish_OnClick(object sender, RoutedEventArgs e)
    {
        PublicMyTweetAsync();
    }

If I check the user login, is correct but send always is false, I've already try without async call, and Tweet.PublishTweet(MyTweet) and TweetAsync.PublishTweet(MyTweet), if anyone can hepl, thanks.