10:54:30,252 PM [testsystem-pekko.actor.default-dispatcher-4] [INFO] Slf4jLogger - Slf4jLogger started 10:54:30,561 PM [testsystem-pekko.actor.default-dispatcher-4] [INFO] CoordinatedShutdown - Running CoordinatedShutdown with reason [ActorSystemTerminateReason] 10:54:30,564 PM [testsystem-pekko.actor.default-dispatcher-4] [INFO] RepointableActorRef - pekkoDeadLetter Message [java.lang.String] from Actor[pekko://testsystem/system/testActor-30#-1749847921] to Actor[pekko://testsystem/user/pingpongactor#294820187] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[pekko://testsystem/user/pingpongactor#294820187] may have terminated unexpectedly. This logging can be turned off or adjusted with configuration settings 'pekko.log-dead-letters' and 'pekko.log-dead-letters-during-shutdown'.