Keep away from Bookabook

I ordered a book from this company in March 2023 and promised delivery in few days. After over 20 emails and calls I was requested, by the company, for my banking detail for a refund in May 2023. They event went as far as confirming receipt of my email and advising the refund will be done in 48 hours on 29 May 2023. To date over 30 attempts to call this company and email them and no response, What are my next steps?