The response received from a further peer node was itself invalid (Invalid reply from remote peer).
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 the logs of the further peer node this response ultimately depended on.
Check which node sent the response (MME, SGW or PGW): the cause belongs to that node's decision.
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