override async public void UpdatePositionAsync(int index, string deviceLanguage,  BusinessLayer.User user)
        {
            // Update the position in the DB
            DataAccessLayer.DAL_Bestellung dal_Bestellung = new DataAccessLayer.DAL_Bestellung();
            this.Positions[index] = await dal_Bestellung.UpdatePositionAsync(this, this.Positions[index ], deviceLanguage,  user);
            this.Wert = this.Positions[index].KpfWert;

        }