Unfair trade practice and denial of refund.

I find a printed tshirt in their instagram and i asked them is that product available and they said that yes the product is available and I sent my address and they send me the qr code for payment. But it was already 7:37 at night and i was not able to pay . But at morning i paid for it . And that time they are saying that it has been sold out and pick any another tshirt but i said I don’t need tshirt you please refund me the amount. And now they are saying that there is no refund policy in our shop i called them and said so many times but they were not ready to refund me the cash.