Timeout error while doing bulk indexing in Elasticsearch EKS.

In our organisation we have Elasticsearch deployed in AWS EKS. From starting of december 2024 we started having problem of timeouts in both API’s get requests and while doing bulk indexing in a scheduled process everyday.

API timeout issue is persistent with some number of requests failing while some passing.
Bulk indexing issue is occasional , sometimes it comes sometimes not.

API timeouts time specified in code: 3.5 to 5 seconds

Bulk indexing timeouts specified in code: 60 seconds

Grafana stats: pod memory,cpu are withing specified limits in yml, there are no spikes.

Pod logs:
master pod: At exact time of issue there are no logs in master before and after issue timestamp there are normal info logs.

kubectl get pods -o wide command provides minimum pod age of 5 days. Suppose we got issue right now , than above command gives minimum AGE attribute of pods among data/master/ingest as 5 days means there are no frequent restarts.

persistant volume stats are also okay.

Please help , how can we fix these timeouts in elasticsearch