IllegalArgumentException: Illegal new producer epoch -1

Hi,

one of our customers ran into this error. It seems to appear every hour.

2021-11-08 12:29:33,149 [group-metadata-manager-0] INFO [GroupMetadataManager brokerId=2] Removed 0 expired offsets in 0 milliseconds. (kafka.coordinator.group.GroupMetadataManager)
2021-11-08 12:29:33,259 [transaction-log-manager-0] ERROR Uncaught exception in scheduled task 'transactionalId-expiration' (kafka.utils.KafkaScheduler)java.lang.IllegalArgumentException: Illegal new producer epoch -1at kafka.coordinator.transaction.TransactionMetadata.prepareTransitionTo(TransactionMetadata.scala:325)at kafka.coordinator.transaction.TransactionMetadata.prepareDead(TransactionMetadata.scala:293)at kafka.coordinator.transaction.TransactionStateManager.$anonfun$enableTransactionalIdExpiration$7(TransactionStateManager.scala:157)at kafka.coordinator.transaction.TransactionMetadata.inLock(TransactionMetadata.scala:188)at kafka.coordinator.transaction.TransactionStateManager.$anonfun$enableTransactionalIdExpiration$6(TransactionStateManager.scala:157)at scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:238)at scala.collection.immutable.List.foreach(List.scala:392)at scala.collection.TraversableLike.map(TraversableLike.scala:238)at scala.collection.TraversableLike.map$(TraversableLike.scala:231)at scala.collection.immutable.List.map(List.scala:298)at kafka.coordinator.transaction.TransactionStateManager.$anonfun$enableTransactionalIdExpiration$3(TransactionStateManager.scala:155)at scala.collection.TraversableLike.$anonfun$flatMap$1(TraversableLike.scala:245)at scala.collection.mutable.HashMap.$anonfun$foreach$1(HashMap.scala:149)at scala.collection.mutable.HashTable.foreachEntry(HashTable.scala:237)at scala.collection.mutable.HashTable.foreachEntry$(HashTable.scala:230)at scala.collection.mutable.HashMap.foreachEntry(HashMap.scala:44)at scala.collection.mutable.HashMap.foreach(HashMap.scala:149)at scala.collection.TraversableLike.flatMap(TraversableLike.scala:245)at scala.collection.TraversableLike.flatMap$(TraversableLike.scala:242)at scala.collection.AbstractTraversable.flatMap(Traversable.scala:108)at kafka.coordinator.transaction.TransactionStateManager.$anonfun$enableTransactionalIdExpiration$2(TransactionStateManager.scala:148)at kafka.coordinator.transaction.TransactionStateManager.$anonfun$enableTransactionalIdExpiration$1(TransactionStateManager.scala:146)at kafka.utils.KafkaScheduler.$anonfun$schedule$2(KafkaScheduler.scala:116)at kafka.utils.CoreUtils$$anon$1.run(CoreUtils.scala:65)at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(ScheduledThreadPoolExecutor.java:180)at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:294)at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)at java.lang.Thread.run(Thread.java:748)

They are using Confluent-Kakfa V 5.5.2. Could this be a bug? Any hint would be much appreciated!

Regards
Mathis