If your voucher isn't accepted, please double-check you are entering the voucher in the correct box - it's very easy to enter it into the Offer Code box by mistake as they look alike. The voucher code box is case-sensitive, and the code has to be entered exactly as printed for it to work. Sorry, we know it's long ! 

If you are using a membership voucher, you need to make sure you log in before you order. Once you've logged in you should be able to see any membership vouchers you've not yet used, and you can automatically add these to your order from there.