A handover/relocation procedure failed partway through (Relocation failure).
Where you see it
In the Cause IE of a GTPv2-C response (Create Session, Modify Bearer, Delete Session…) on S11, S5 or S8.
What to check
Check both the source and target node's logs for the specific handover failure reason.
Check which node sent the response (MME, SGW or PGW): the cause belongs to that node's decision.
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