disappointed

I did an online shopping on the 4th of this months. the funds where debited from my account however yesterday i got an email stating that 2 of my items where out of stock, what pains me is that those 2 items where the most needed ones because it was someone present. what disappointing is why didn't they substitute with something similar and worse they didnt even refund me my money. why didnt they take off the stuff that was out of stock online coz i would have looked for something else, now i will miss my sisters birthday because of that