Fifth Generation (5G) standards specify use of a Subscription Concealed Identifier (SUCI) (i.e. a concealed identity) for a user equipment (UE) during initial registration, where the SUCI is derived from a Subscription Permanent Identifier (SUPI) of the UE. Given the identity concealment and use of different identities on different interfaces in a 5G network, maintaining subscriber state with a stateless network architecture may be challenging. Accordingly, one or more techniques and mechanisms are provided herein for subscriber management with a stateless network architecture in a 5G network, even without the need to maintain intermediate states of a UE in an external data store. The one or more techniques and mechanisms may be provided in relation to processing of Next Generation (NG) Application Protocol (NGAP) signaling messages at an access and mobility management function (AMF), and in particular, in relation to a registration procedure for the UE.