Online orders cancelation due to stock availability after placing orders

What's the use of having an online shopping option if the online inventory doesn't match the on hand stock that you have.

It's really pointless for us as customers to go online and place an order online for your order to be canceled after a few days because there's no stock.

If it was something happening for 1st or 2nd time I'd understand but this happening to me for the 5th time this year just means you're not even doing anything about it