Every time when I launch a job, it seeks 0th Offset. So, I am getting messages from beginning. Is this a bug?

Since Aug 2020, you could use partitionOffsets on the builder to tell the reader that it should start reading from the offset stored in Kafka for the consumer group ID

return new KafkaItemReaderBuilder<String, String>()
    .partitions(0)
    .consumerProperties(props)
    .name("customers-reader")
    .saveState(true)
    .topic("test-consumer")
    .partitionOffsets(new HashMap<>()) // <--- here
    .build();

see this link