Store DataPicker in SQLite [xamarin]

I am in Xamarin.Forms, I can not store the date of a DataPicker in the database. This is the class of the database:

public DateTime Fecha
    {
        get;
        set;
    }
    public string FechaModificada
    {
        get
        {
            return string.Format("{0:dd-MM-yyyy HH:MM}", Fecha);
        }
    }

And this is the XAML code snippet:

<DatePicker x:Name="HoraFinal"
                        MinimumDate="1/1/1999" 
                        MaximumDate="1/1/3000" 
                        Grid.Row="2" Grid.Column="0" 
                        HorizontalOptions="Start" VerticalOptions="Center"
                        DateSelected="Fecha_Selected"
                        />
            <Entry Text="{Binding Fecha, Source={x:Reference HoraFinal}, Mode=TwoWay}"  />

And in the programming part I made an alert to see if I picked up the date well.

//Click en hora
    DateTime ultima;
    async void Fecha_Selected(object sender, Xamarin.Forms.DateChangedEventArgs e)
    {
        ultima = e.NewDate;
        var fechaMostrar = e.NewDate.ToString("D");
        await DisplayAlert("DatePicker", fechaMostrar, "Aceptar");

It picks it up well but then it does not store the date well in the database. Stores with the value 01/01/0001. How do I get the DataPicker date and store it correctly in the database ??????