Method for performing a procedure related to AMF registration by UDM in wireless communication system and apparatus for same

A user equipment (UE) for performing a registration related procedure of an access and mobility management function (AMF), the UE comprising:

• a transceiver;
• at least one processor;
• and
• at least one computer memory operably connectable to the at least one processor and storing instructions that, when executed by the at least one processor, perform operations comprising:
• transmitting, to a first AMF, a first message related to a registration, the first message being transmitted over one of 3GPP access and non-3GPP access;
• and
• receiving a deregistration request message from a second AMF being as a serving AMF of the UE,
• wherein the deregistration request message is received from the second AMF, when Unified Data Management (UDM) transmitted a deregistration related message to the second AMF, based on that an access type of the first AMF is the same as an access type of the second AMF, and
• wherein the deregistration request message is received due to a withdraw of a subscriber's context by UDM (Unified Data Management).