Only advising out of stock after payment made

I phoned Boardmaster on Thusday 17th Dec, spoke to a gent by the name Darryl. Ordered 50 sheets of 9mm commercial ply. He e-mailed me a quotation. I immediately made eft payment the same morning and e-mailed the payment advice to Darryl. I was told they cannot release the stock until the payment reflects, which would have been Friday 18th December afternoon. On Monday 21st December I phoned Darryl, to ensure the invoice was going to have the correct information for the border post. I sent a transporter from Swaziland to collect. On Tuesday 22nd Dec after the transporter complained his truck had been standing at Boardmaster for over an hour, I phoned Darryl to ask him why they had not loaded the truck since it had to return to Swaziland, only to be told they had sold the stock to someone else and could not load for me. Darrly told me he would be able to supply me in January nut it would be at a higher price. The least I would expect is that they honor the price I paid and supply me in January since they sold the stock after I had made payment. I am also out of pocket for the transport since the truck will be returning empty.