Refuse to rectify their error

On 25/8 I collected my order for a cellphone cover and screenguard combo. I got home and immediately put the screenguard on, which fitted perfectly. Then I took out the cover and it was almost a centimetre too long. So it was obviously the wrong cover for my phone. I obviously couldn't request a refund because I had already installed the screenguard, so I asked for the correct cover to be sent to me. Now I'm being told that Takealot can't fix this problem because the supplier is out of stock. (And I checked - the same supplier is still advertising phone covers for my phone on Takealot, so someone is lying) I am now left out of pocket and with a useless cover sent to me in error by the supplier and Takealot, yet nobody is prepared the rectify THEIR mistake! I'm just being ignored now.