public void When_NewAccountIsCreated_Expect_InitialBalance()
 {
     _virtalCashCardWithBalance.CheckBalance(_validPinNumber).Should().Be(500.00M);
 }
        public void When_NoPinNumberIsProvidedToCheckBalance_Expect_InvalidOperation()
        {
            Action action = () => _virtalCashCard.CheckBalance(string.Empty);

            action.Should().Throw <ArgumentException>().WithMessage("Pin number must be provided");
        }