Exchange or I want a refund!!

I made a purchase on the Mr price app on 07/01/2021 order number:***, the order included 3 pairs of 3 secret socks. Last week I went to collect the order and when I got home I realised the 3 pairs of socks weren't there instead there was one pair of normal socks which I didn't order. Mr price intentionally put in the wrong socks instead of refunding my money, if the socks were out of stock they didn't even bother to notify and ask me what I want instead they put a ugly pair of socks that doesn't even amount to the value of socks are ordered. Today when I went to Mr price in Fleurdal, I was told if I wanted an exchange for the correct socks I need to top up or get a voucher or buy airtime but they can't refund me. If I wanted a voucher I would have bought one same applies to airtime. I want my money refunded back into my account please or give me the 3 pairs I originally ordered I don't want these ugly socks you sent me! I don't appreciate what you have done!!! All online stores notify their customers when they can't deliver a product, YOU HAVE NO RIGHT TO DECIDE ON THE CUSTOMER'S BEHALF!!!