AWS managed OpenSearch Audit logs "audit_request_remote_address": "__IP__",

Versions (relevant - OpenSearch/Dashboard/Server OS/Browser):
OpenSearch 2.17

Describe the issue:
I have AWS managed OpenSearch, I’m trying to figure out which pods in my EKS cluster are getting 400x errors. the pods are behined NLB. I have enabled Audit logs but the logs doesn’t show the the ip address that makes the errors. it’s shown as “audit_request_remote_address”: "IP ".
Can someone help?

Configuration:
Not sure if it’s related but this the cluster security configuration:
Required HTTPS: Yes
Encryption at rest: Yes
AWS KMS key: Yes