Facing issue with Logstash 7.6.2 [logstash.outputs.elasticsearch][.monitoring-logstash] Encountered a retryable error

I have upgraded logstash and now I am using logstash version 7.6.2. My elasticsearch version is 6.8.13. After upgrade, I see a lot of error logs related to monitoring-logstash pipeline. The log of this error is given below:

[ERROR][logstash.outputs.elasticsearch][.monitoring-logstash] Encountered a retryable error. Will Retry with exponential backoff {:code=>400, :url=>"http://elasticsearch:9200/_monitoring/bulk?system_id=logstash&system_api_version=7&interval=1s"}

Can anyone guide me how to slove this? I have tried to search that issue a lot but could not find solution yet. Previously when I was using the logstash 6.8,4 I did not face such issue.

My configuration in logstash.yml is given below:

    node.name: "logstash"

    xpack.monitoring.elasticsearch.username: "logstash_system"
    xpack.monitoring.elasticsearch.password: "logstash_system"

    xpack.monitoring.elasticsearch.hosts: [
      "http://elasticsearch:9200"
    ]

    xpack.monitoring.enabled: true

Welcome to our community! :smiley:

You should look to upgrade your Elasticsearch as well if you can.