Complete inconvenience from Takealot.com

Bought an Air conditioner for R13349 on 25 November 2020. Only the indoor unit was delivered on 28 November 2020 despite the advert saying that the air conditioner comes with both indoor and outdoor units. When I informed Takealot.com that the unit is incomplete and that I need them to deliver a complete unit, they informed me that the product is out of stock and that they will credit my account. Today it’s 4 December, they haven’t collected their incomplete unit and they haven’t returned my money. Now I can’t even buy another unit elsewhere, they’re holding on to my money. I’m suffering because of their inefficiencies. Why did they even deliver an incomplete product in the first place? Why hold on to my money when it’s not my fault that they delivered an incomplete product?