Oh no! No worries, you have some options depending on when you placed your order.
If you placed your order after 15:00 (3PM UK GMT) then your order will be picked the following working day, so please email email@example.com ASAP and they will be able to cancel your order for you so you can place a new order.
We cannot change the order because the stock fluctuates every minute due to global sales so the product you are asking for might be out of stock.
If you have placed an order and only just noticed after it has been dispatched then please return the goods unworn and in original packing and we can then refund you and you can then place a new order and get the correct item