Provided in one disclosure of the present specification is an operation method of a relay user equipment (UE) for a remote UE. The method may comprise a step in which the relay UE receives, from a base station, a radio resource control (RRC) reconfiguration message or an RRC connection reconfiguration message. The RRC reconfiguration message or the RRC connection reconfiguration message may include identification information of a data radio bearer (DRB) shared with the remote UE and information on a protocol data unit (PDU) session which must be deleted or released in the DRB. The method may comprise a step in which an access stratum (AS) layer of the relay UE relays, to a non-access stratum (NAS) layer, information that a user plane (UP) connection of the PDU session was released, on the basis of the received RRC reconfiguration message or the RRC connection reconfiguration message.