Fail to honor their terms and conditions to provide items purchased or refund me

In July 2023 I bought another of items of their auction and paid for the items, courier service and insurance of the package in transit. I have been following up with them daily and it is now 4 months later and they have ignored all my commuinication and failed to honor their terms and conditions. Previously they advised me that the order was in transit yet nothing arrived. I have also asked to be refunded but they ignore this request as wel - they advertise items expect you to pay immediately and then fail to send the items - This is a ****.