No refund on the item not yet received, of which i was not be informed before making payment

I was looking for a company that sells the paving bricks around Polokwane, when I check on the google I found this VTB G.O.C Brick World (pty) Ltd on their Facebook page. I spoke to them and the price was reasonable, in fact, they said is the black Friday special, I was convinced and went to their place of business on the 16th of November 2020 and paid for that material and there was no stock at that time. I was number 18 on the waiting list, due to other unforeseen circumstances ( family emergency) that require money. I called them the following to request for refund. the Lady there told me that she will speak to the manager and will call me thereafter. after two days, I went to them to find out about my request and that lady said she did not speak to the manager yet, she promised to call us. after a day, I went again to find out what was the problem, I found the lady with that manager. That manager was so rude to me when the lady said I am the one who needs to be refunded. He said their policy does not allow a refund, he mentioned that he already bought material to produce those bricks and he won't be able to give me the small change that I call money. after our verbal fighting, he further mentioned that he doesn't promise when he will be able to give that money back with the attitude. I was not informed before hand about the no refund policy, I was surprised to see it on the other paper called estimate that was given to me together with the invoice. to me, they are unfair as there were no sales, exchange of transactions did not take place as I didn't get anything yet. Please assist me in this regards