Voucher not refunded yet no order

I tried placing order on steers website and I had voucher so I entered it and proceeded to pay remaining amount through card. The card processing page where you meant to enter card details threw an error so I reloaded the page. Took me back to the menu to reselect the items but now the voucher won't work it's used yet the order didn't go through. Called them was told to email and it will be forwarded to voucher department. Everyday since then I have been calling I'm always told they will contact me to refund my voucher yet nothing. Its been days my money voucher gone just like that. The restaurant I was attempting to order from is Steers Broadacres.