Leisure books refuses to refund me , Do not buy from them

I bought books online in September 2018, leisure books then sent me an email and indicated that they did not have stock. In November, I asked them to refund me. To date, March 2019, they still have not refunded me. When I follow up, via email, the email comes back indicating that it has been marked as "Not important" by the recipient. ID270920. Please assist.