A device includes a processor and memory storing a computer program that causes the processor to perform operations including (A) acquiring an address indicating a delivery destination of a package, and first attribute information indicating an attribute of a stopping position where an autonomous vehicle delivering the package stops at the delivery destination, (B) determining a side from which the package is to be unloaded at the delivery destination, out of a plurality of sides of the autonomous vehicle, based on the address and the first attribute information, and (C) outputting management information in which identification information for identifying the package is associated with the determined side.