False Advertising

Am failing to understand why hifi corp still advertise the Sansui 48 ich full HD selling for R1999 on their website if they are out of stock and won't have the device anymore, yesterday when I checked hi-fi Corp Centurion they had stock when I went to hifi corp Carnival Mall to double check before I go to Centurion we were told that they didn't have stock even when their website shows that they do have stock, what I want to know is why is the adv still on their website