Worst experience - no refund issued

Worse shop ever in my life. Worst customer service. They are rouges. I purchased a shoes online on Friday and it was delivered on Monday, when I tried it on it was not fitting I went on that Tuesday to ask for a refund . They kept saying no cash and mind you this was a Monday afternoon, they said to come the next day. I went on the next day and then they still say there's no cash and they can do an EFT payment which will take 10 days, I asked them what is the guarantee it will come to my account they said there is no guarantee which means this so sketchy and not even a legit company. I only have 30 days to get a refund. The way they act like they doing us a favour and it's their money. Someone please assist