https://www.consumer.ftc.gov/article...ed-merchandise
Q. Am I obligated to return or pay for merchandise I never ordered?
A. No. If you receive merchandise that you didn’t order, you have a legal right to keep it as a free gift.
Q. Must I notify the seller if I keep unordered merchandise without paying for it?
A. Although you have no legal obligation to notify the seller, you may write the seller and offer to return the merchadise, provided the seller pays for shipping and handling.