ESM cause (LTE NAS)3GPP TS 24.301 §9.9.4.4 and Annex B
What it means
User authentication failed: the PGW or an external AAA server rejected the user (PAP/CHAP, RADIUS) for this APN.
Where you see it
In LTE NAS PDN connectivity reject, bearer resource reject or EPS bearer deactivation.
What to check
Check the APN's authentication settings and the AAA server answer.
Check the GTPv2 Create Session Response and the HSS APN configuration for the same APN.
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