One embodiment of the present specification provides a method comprising the steps of: transferring, by an access stratum (AS) layer of a user device, information on a communication state with another user device to an upper layer through a non-access stratum (NAS) layer, while the user device communicates with the other user device through a direct communication path; receiving, by the NAS layer, a notification on a change of the communication path from the upper layer; commanding, by the NAS layer, the AS layer to perform a radio resource control (RRC) connection procedure in a request type (call type) which indicates the purpose of service continuity in accordance with the change of the communication path; and transmitting, by the AS layer, an RRC connection request message including a connection request type (establishment cause) which indicates the purpose of the service continuity of the proximity service to a base station.