Refunds WILL take forever, Orders NEVER show up

In December I order an item on pre -order which meant 12 - 17 working days delivery, Late January after various enquiries for my order they advised that they did not receive my item. They then gave me a voucher for the value and I immediately redeemed for another item. I was then informed they could not supply this item either. They then offered me yet another voucher. I declined and requested a refund. I have sent my bank details to them 3 times already. Now their reply is that they can only refund me once they get funds in, they have had my funds since December. Totally unacceptable