Not happy with the company

On the 27April 2022 an amount of R6300 was paid to booking.com by error and i also have a pop. I have been trying to contact the business and sent them the proof of payments to check the payment so they can send it back to me with no luck. i even phoned the bank i use to confirm the payment and they confirmed the transaction was successful. Up to now i still do not have a solution to my problem