LTE: Tracking Area Update Reject

If the Tracking Area Updating cannot be accepted by the network, the MME sends a TRACKING AREA UPDATE REJECT message to the UE including an appropriate EMM cause

If the MME locally deactivates EPS bearer contexts for the UE and no active EPS bearer contexts remain for the UE, the MME shall send the TRACKING AREA UPDATE REJECT message including the EMM cause value #10 "Implicitly detached"

If the TRACKING AREA UPDATE REQUEST is rejected due to NAS level congestion control, the network shall set the EMM cause value to #22 "congestion" and assign a back-off timer T3346. Refer to 3GPP TS 24.301 for all other EMM cause values

Example: TRACKING AREA UPDATE REJECT - cause: PLMN not allowed