Shocking online adverti*****t and service

On 18 March 2020 We have bought a PS4 500GB online. Advertised as R3549. We have paid, they have accepted the payment and released the PS4 for delivery. Three days later this order was cancelled by incredible connection's back office. We only found out that they have cancelled the order and will not honour the transaction after two days trying to phone the customer service line.

The customer service line informed that management instructed the cancellation of the order and that they are not allowed to give the management contact details out as they are working from home.

How do you accept my payment, release the goods and then cancel as you please, This is not acceptable.