I am Liza Smit

We ordered & paid for the book I am Liza Smit in July 2018. The book was never delivered & when I enquired about the order I was told that they were out of stock. By December they still had no stock. I cancelled the order. They asked for Bank Details & confirmation from the Bank. I sent the Bank Confirmation letter in December 2018 and January 2019. It is now March and still no refund. How do I get them to refund us. Thank you. Helen Trauernicht