Laptop Purchased online

I understand that the store is an online store, so that means it should be updated frequently regardless if the products are purchased in store or from the website, on Saturday the 10 Feb 2018 I purchased a Lenovo i5 Laptop that was on special, assuming they still had stock which is what the website said, i purchased it did an eft an got the confirmation that my order has went through, today I call them to follow up as to why I did not get the confirmation to fetch it, they tell me they are out of stock and have to wait until March to get one, I have heard nothing but good praise about this business, as a first time customer this is what happens, what gets to me is why still have it available online, when i called on saturday the salesperson said i could come purchase the laptop instore and do an eft but could not take it until the money clears hence why i did it online, now they suggest i wait until march or pay R2000 extra for a different laptop, when none of it is my fault since i was under the impression that their was still stock available, some help would be appreciated. Thanks