A method for managing information obtains, through a first communication circuit, a locker identifier and a user identifier from a locker into which a user card has been inserted, obtaining, through a second communication circuit, a machine identifier and a key identifier from a machine that has read the key identifier, and outputting, using a first database that associates the locker identifier and the key identifier with each other and the obtained locker identifier and user identifier, the user identifier corresponding to the key identifier to the machine to set the user identifier to the machine.