Pay in full then they cancelled order

Placed an order and paid in full on the 10/12/2025. Delivery scheduled for the 19th. On the 18th I received a SMS cancelling my order and stating I will be refunded by the 01/01/2026. Disgusting service. How can you justify keeping my money for this length of time. You had stock when I paid. Really disappointed that a company of this calibre can't deliver as agreed