What is it called when you receive something from a company that you did not order?

When you receive something from a company that you did not order, it is often referred to as an "unsolicited shipment" or "unrequested item." This can occur due to shipping errors, promotional giveaways, or billing mistakes. In many cases, recipients are advised to contact the company to clarify the situation and determine if they should return the item or if it is theirs to keep.