Kafka: Continuously getting FETCH_SESSION_ID_NOT_FOUND

Increase the value of max.incremental.fetch.session.cache.slots. The default value is 1K, in my case I have increased it to 10K and it fixed.

This is not an error, it's INFO and it's telling you that you are connected but it can't fetch a session id because there's none to fetch.

It's normal to see this message and the flushing message in the log.