TextBox не изменяет свойство

TextBox находится в GroupBox, который находится в вложенном в ScrollViever Grid'е. Перепробовал уже все, так как количество стержней динамически меняется нет возможности задать через Xaml

class RodTextBox : TextBox
{
    public RodTextBox(string text,string propertyName, Rod rod)
    {
        Text = text;
        TextWrapping = TextWrapping.Wrap;
        addBinding(propertyName ,rod);
        DataContext = rod;
        GotFocus += clearTextOnFocus;
    }
    public void addBinding(string propertyName, Rod rod )
    {

        Binding myBinding = new Binding($"{propertyName}");
        myBinding.Source = rod;
        myBinding.UpdateSourceTrigger = UpdateSourceTrigger.LostFocus;
        myBinding.Mode = BindingMode.TwoWay;
        SetBinding(TextBlock.TextProperty, myBinding);
    }
    public void clearTextOnFocus(object sender, RoutedEventArgs e)
    {
        Text = String.Empty;
    }
   
}
class Rod : INotifyPropertyChanged
{

    public Rod (int number, int sqare,int length,int elastic)
    {
        Number = number;
        Sqare = sqare;
        Length = length;
        Elastic = elastic;
    }
    int _Number;
    int _Sqare;
    int _Length;
    int _Elastic;
    public int Number
    {
        get
        {
            return _Number;
        }
        set
        {
            _Number = value;
            NotifyPropertyChanged("Number");
        }
    }
    public int Sqare
    {
        get
        {
            return _Sqare;
        }
        set
        {
            _Sqare = value;
            NotifyPropertyChanged("Sqare");
        }
    }
    public int Elastic
    {
        get
        {
            return _Elastic;
        }
        set
        {
            _Elastic = value;
            NotifyPropertyChanged("Elastic");
        }
    }
    public int Length
    {
        get
        {
            return _Length;
        }
        set
        {
            _Length = value;
            NotifyPropertyChanged("Length");
        }
    }
    public event PropertyChangedEventHandler PropertyChanged;

    private void NotifyPropertyChanged([CallerMemberName] String propertyName = "")
    {
        PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
    }