Dis-Chem online order not fulfilled

I placed an online order on Dis-Chem website and received proof of payment and order confirmation.

Three days later I receive a call from a nearby store claiming they do not have stock of the item I already paid for.

My problem is that I didn't order from a store and did not make payment to a local store, I ordered and paid on the national Dis-Chem online website.

I have not received any additional electronic communication from Dis-Chem Online after the order and payment confirmation.

Point One: An online order should not be subject to stock level at a nearby branch.

Point Two: An online order should be honored as confirmed.

Point Three: If for some acceptable reason (local out of stock is NOT an acceptable reason) the product is suddenly not available, direct client contact should be made by Dis-chem Online with option for alternative or refund.

Further, The online order includes a delivery charge.

Surely if Dis-Chem online has the product available it should be able to source from elsewhere in the country independently of what is on shelf in a nearby branch and use the delivery charge to deliver to the client. Or why is there a delivery charge?