[INFO] [pekkoDeadLetter][08/30/2025 10:23:57.137] [testsystem-pekko.actor.default-dispatcher-6] [pekko://testsystem/user/pingpongactor] Message [java.lang.String] from Actor[pekko://testsystem/system/testActor-13#-1969015428] to Actor[pekko://testsystem/user/pingpongactor#212031351] was not delivered. [1] dead letters encountered. If this is not an expected behavior then Actor[pekko://testsystem/user/pingpongactor#212031351] 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'.
[INFO] [08/30/2025 10:23:57.138] [main] [CoordinatedShutdown(pekko://testsystem)] Running CoordinatedShutdown with reason [ActorSystemTerminateReason]