Systems and techniques for handling a protocol data unit (PDU) session by a wireless device implementing an access stratum (AS) layer and a non-access stratum (NAS) layer in a wireless communication system. An example technique includes determining, by the AS layer of the wireless device, whether a user plane for the PDU session is activated or released; transferring, by the AS layer and to the NAS layer of the wireless device based on a determination that the user plane for the PDU session is activated, first information indicating that the user plane for the PDU session is activated; and transferring, by the AS layer and to the NAS layer of the wireless device based on a determination that the user plane for the PDU session is released, second information indicating that the user plane for the PDU session is released.