If purchased directly from Apple or online Apple Store, in most countries/regions you have 14-days within which you can unconditionally return an undamaged item for exchange or refund.
If purchased online from Apple, you will have received confirmation or order and your invoice via email. These email messages will include contact details should you have any queries, or need to return items for refund or exchange.
Act quickly to initiate your return - as, given that you purchase was made on 6th February, you are fast approaching the 14-day deadline (i.e., 20th February). Should you choose to do so, you can also return the Pencil to a physical Apple Store; you will require your purchase invoice.