Poor service delivery

I ordered a Samsung Boracay Wall Split 9000 Btu/hr Non Inverter Air Conditioner on 29/11/19. I had to call them to get an invoice( not easy to get hold of this company on the phone). I was assured that I would receive my delivery within 7 days. Delivery did not take place. I was then told that I would receive the unit by today. This is 11 days post-purchase. Still no delivery!? I received an e-mail this morning saying that they are having issues with stock? Who sells a product online without having enough stock in place. Please note that the full amount was paid upfront. AC direct where is my AC?