No Return Adress
An anonymous package was sent to the recipient: it was not addressed or labeled with the sender’s name. A UPS package is usually collected from the sender’s house and needs a return address for shipping; UPS does not allow anonymous shipping.
In the case that you don’t want the recipient or UPS to know who sent the package you are sending, you can leave it at a UPS depot across the state. What would make anyone do that?