Unfortunately we are unable to offer an exchange for an item you have ordered online and wish to return to the warehouse.
You can however, pop into your nearest New Look store, where they can process a refund for the item, and either locate the item from their own stock, or place a new order for you. All you'll need with you to return the item, is your order number and original payment card.
You can check yourself if your local store has stock of the specific item, by using the 'FIND IN STORE' button on the web page of the item you want. More info on how to do that here.