/// <summary>
        /// Refunds completely the paid payment.
        /// </summary>
        /// <param name="onlinePayment"></param>
        /// <param name="verifyResult"></param>
        public static IPaymentRefundResult RefundCompletely(this IOnlinePayment onlinePayment, IPaymentVerifyResult verifyResult)
        {
            if (onlinePayment == null)
            {
                throw new ArgumentNullException(nameof(onlinePayment));
            }
            if (verifyResult == null)
            {
                throw new ArgumentNullException(nameof(verifyResult));
            }

            return(onlinePayment.Refund(new RefundInvoice(verifyResult.TrackingNumber)));
        }