Takealot claiming to be out of stock, but still advertising after cancelling my order

I ordered an item from Takealot. The following day, I receive an email stating that they have cancelled my order due to them being out of stock. I ordered the item on one of their sales, and there was definitely still stock reflecting when I completed my purchase (*** items left showed after I completed my order).

The following day, I go onto Takealot and see the same tablet being advertised again, different price, but stock available (no stock limit stated).

How can you cancel my order due to no stock, but then sell the same item the next day, in stock, at a different price? I am extremely unhappy about this.