The most common reasons for this are:
One of the items you are trying to buy has already been discounted. Discount codes will only work on full price products. They also can not be used to buy subscriptions.
The code is not applicable to the product that you are trying to purchase. Most of our codes are only valid for a particular product or range (e.g. Summer Range). Please double check that you are using the code on a valid product.
The code has been entered incorrectly. To ensure the code has been typed correctly, please copy and paste the code into the voucher code box, and click 'Apply Coupon'.
The code has expired. Most codes are only valid for a limited period. The period should be stated where you received the code.