Visual Studio Значение “maxValue” должно быть больше нуля

Весь код

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using System.Windows.Media.Animation;
namespace WpfApp1
{
/// <summary>
/// Interaction logic for MainPage.xaml
/// </summary>
public partial class MainWindow : Window
{
    Random random = new Random();
    public MainWindow()
    {
        InitializeComponent();
    }
    private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
    {
    }
    private void startButton_Click(object sender, RoutedEventArgs e)
    {
        AddEnemy();
    }
    private void AddEnemy()
    {   
        ContentControl enemy=new ContentControl();
        enemy.Template = Resources["EnemyTemplate"] as ControlTemplate;
        AnimateEnemy(enemy, 0, playArea.ActualWidth - 100, "(Canvas.Left)");
        AnimateEnemy(enemy, random.Next((int)playArea.ActualHeight - 1),
            random.Next((int)playArea.ActualHeight - 1), "(Canvas.Top)");
        playArea.Children.Add(enemy);
    }
    private void AnimateEnemy(ContentControl enemy, double from, double to, string propertyToAnimate)
    {
        Storyboard storyboard = new Storyboard() { AutoReverse = true, RepeatBehavior = RepeatBehavior.Forever };
        DoubleAnimation animation = new DoubleAnimation()
        {
            From = from,
            To = to,
            Duration = new Duration(TimeSpan.FromSeconds(random.Next(4, 6))),
        };
        Storyboard.SetTarget(animation, enemy);
        Storyboard.SetTargetProperty(animation, new PropertyPath(propertyToAnimate));
        storyboard.Children.Add(animation);
        storyboard.Begin();
    }

}

}

При запуске ошибка

System.ArgumentOutOfRangeException: 'Значение "maxValue" должно быть больше нуля.'

В свойствах высота/ширина установлены на авто.

Значения переменных В чем может быть ошибка?