public async void CancelPaymentAsync_ShouldReturnNotFound()
{
var accountId = Guid.NewGuid();
var paymentId = Guid.NewGuid();
var mediator = new Mock <IMediator>();
mediator.Setup(m => m.Send(It.IsAny <CancelPaymentCommand>(), It.IsAny <CancellationToken>())).Throws(new KeyNotFoundException());
var controller = new PaymentController(mediator.Object);
var result = await controller.CancelPaymentAsync(accountId, paymentId, new CancelReasonDTO { Reason = "cancel" });
Assert.True(result is NotFoundResult);
}