How to commit Kafka offset manually using Spring Cloud Stream reactive functions

I'm trying to commit offset manually in Kafka consumer by using java functions(Consumer) in Spring cloud stream, but the offset is getting committed after java function executed successfully.

enable.auto.commit: false
ack-mode: MANUAL_IMMEDIATE

@Bean
public Consumer<KStream<String, String>> process() {
 
     return stream -> stream.foreach((key, value) -> {
            
            logger.info("Key: " + key + " Value: " + key);

     }

}

Can some one help to provide the correct configuration for manual commit offset in Spring cloud kafka consumer function