06:28:35,741 PM [testsystem-pekko.actor.default-dispatcher-6] [INFO] Slf4jLogger - Slf4jLogger started
06:28:36,138 PM [testsystem-pekko.actor.default-dispatcher-6] [INFO] RepointableActorRef -  pekkoDeadLetter Message [java.lang.String] from Actor[pekko://testsystem/system/testActor-51#534168503] to Actor[pekko://testsystem/user/pingpongactor#-1116831425] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[pekko://testsystem/user/pingpongactor#-1116831425] 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'.
06:28:36,142 PM [testsystem-pekko.actor.default-dispatcher-6] [INFO] CoordinatedShutdown - Running CoordinatedShutdown with reason [ActorSystemTerminateReason]