Incorrect item received. Never consented to Takealot changing the item without my go ahead.

Ordered a LG 27" GL650F monitor and received a LG QN600 monitor. When I opened the box there was a letter saying they did not have my selected item in stock so they "upgraded" my order to this item. Firstly: This is not what I order and no one contacted me to confirm whether I would be happy with a different monitor than selected. Secondly: This is NOT AN UPGRADE. The specs of this monitor is much lower (to say the least) than the one I ordered. Also, the customer manual disc is not even in a cover/envelope. It's scratched as though its not even new. I need to be refunded asap. Very dissapointed with the service received.