Advertised online yet no stoc****

Placed an order online on 6 December 2019 for an item they advertised will be delivered between 2 and 5 working days. Since I saw nothing happening on the tracking of the order on the 4th working day I submitted a complaint to them which was only responded to late on the final day of delivery to say the item was out of stock and their supplier cannot obtain more as the game was discontinued. I checked their site and the item was still being advertised at that point! Now I get told via email that the amount I paid can be paid back to me yet the person handling this does not tell me how or when this will happen. Very unprofessional business conduct.