EMM cause #13 Roaming not allowed in this tracking area
EMM cause (LTE NAS)3GPP TS 24.301 §9.9.3.9 and Annex A
What it means
Roaming not allowed in this tracking area: the subscriber can roam in this network but not in this area.
Where you see it
In LTE NAS Attach reject, Tracking area update reject, Service reject or Detach request.
What to check
Check regional roaming restrictions for this visited network.
Look at the S6a (MME↔HSS) and S11 messages just before the reject: they usually show the real trigger.
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