ESM cause (LTE NAS)3GPP TS 24.301 §9.9.4.4 and Annex B
What it means
PDN type IPv4 only allowed: the phone asked for IPv6 or dual stack but only IPv4 is allowed for this APN.
Where you see it
In LTE NAS PDN connectivity reject, bearer resource reject or EPS bearer deactivation.
What to check
Normal if the APN is IPv4-only; otherwise check the PDN type in the HSS APN configuration.
Check the GTPv2 Create Session Response and the HSS APN configuration for the same APN.
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