08:42:34,969 PM [testsystem-pekko.actor.default-dispatcher-6] [INFO] Slf4jLogger - Slf4jLogger started
08:42:35,274 PM [testsystem-pekko.actor.default-dispatcher-6] [INFO] RepointableActorRef -  pekkoDeadLetter Message [java.lang.String] from Actor[pekko://testsystem/system/testActor-13#1489829778] to Actor[pekko://testsystem/user/pingpongactor#-840146632] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[pekko://testsystem/user/pingpongactor#-840146632] 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'.