Question: What happens when a UE initiates a de-registration procedure in a cell belonging to an SNPN with a non-globally-unique SNPN identity for which the UE has no valid subscription?
Option 1: The network shall initiate the de-registration procedure and send a DEREGISTRATION REQUEST message including the 5GMM cause #74 "Temporarily not authorized for this SNPN".
Option 2: The network shall reject the de-registration request and send an error message to the UE.
Option 3: The network shall ignore the de-registration request and continue with the current registration state.
Option 4: The network shall initiate a new registration procedure for the UE.
Explanation: According to the text, if the UE initiates a de-registration procedure in a cell belonging to an SNPN with a non-globally-unique SNPN identity for which the UE has no valid subscription, and the de-registration procedure is not due to "switch off", the network shall initiate the de-registration procedure. The AMF shall send a DEREGISTRATION REQUEST message including the 5GMM cause #74 "Temporarily not authorized for this SNPN".