log4j cannot write log in kafka consumer - scala

Question

I need to write logs in a kafka consummer but i obtain this error :
2020-03-22 22:22:20 DEBUG [Producer clientId=producer-1] Starting Kafka producer I/O thread.
2020-03-22 22:22:20 DEBUG [Producer clientId=producer-1] Initialize connection to node localhost:9092
(id: -1 rack: null) for sending metadata request
2020-03-22 22:22:20 DEBUG [Producer clientId=producer-1] Initiating connection to node localhost:9092
(id: -1 rack: null) using address localhost/127.0.0.1
log4j.properties :
log4j.logger.logGen=TRACE, Kafka
log4j.appender.Kafka=org.apache.kafka.log4jappender.KafkaLog4jAppender
log4j.appender.Kafka.topic=kafka
log4j.appender.Kafka.brokerList=localhost:9092
log4j.appender.Kafka.layout=org.apache.log4j.PatternLayout
log4j.appender.Kafka.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %m%n
KafkaClass.scala
import org.apache.log4j._
object KafkaClass extends App {
val logger = Logger.getLogger(this.getClass.getName)
logger.info("kafka info")
logger.error("kafka error")
logger.warn("kafka warn")
}
I don't see what is the problem, thank you for you help
Update :
I have this message console :
2020-03-24 14:27:17 DEBUG [Producer clientId=producer-1] Starting Kafka producer I/O thread.
2020-03-24 14:27:17 DEBUG [Producer clientId=producer-1] Initialize connection to node localhost:9092 (id: -1 rack: null) for sending metadata request
2020-03-24 14:27:17 DEBUG [Producer clientId=producer-1] Initiating connection to node localhost:9092 (id: -1 rack: null) using address localhost/127.0.0.1
2020-03-24 14:27:17 DEBUG Added sensor with name node--1.bytes-sent
2020-03-24 14:27:17 DEBUG Added sensor with name node--1.bytes-received
2020-03-24 14:27:17 DEBUG Added sensor with name node--1.latency
2020-03-24 14:27:17 DEBUG [Producer clientId=producer-1] Created socket with SO_RCVBUF = 32768, SO_SNDBUF = 131072, SO_TIMEOUT = 0 to node -1
but still don't receive message in the consumer