According to Apple Refund Policy:
You have 14 calendar days to return an item from the date you received it.
Only items that have been purchased directly from Apple, either online or at an Apple Retail Store, can be returned to Apple. Apple products purchased through other retailers must be returned in accordance with their respective returns and refunds policy.
Please ensure that the item you're returning is repackaged with all the cords, adapters and documentation that were included when you received it.
More information HERE