Akka.net supervision not resuming actor

TestAkka.cs

using System;
using Akka.Actor;

namespace AkkaSample
{
    class Program
    {
        static void Main(string[] args)
        {
            // todo find out how to inject dependancies into actors

            using (var sys = ActorSystem.Create("games"))
            {
                var counter = sys.ActorOf(Props.Create<ArrayCounter>());
                counter.Tell(new [] {"cat", "mouses", "four", "five", null, "humpty dumpty", "six", "seven" });
                Console.ReadLine();
                counter.Tell("stop", ActorRefs.NoSender);
            }
        }        
    }

    public class ArrayCounter : UntypedActor
    {
        protected override SupervisorStrategy SupervisorStrategy()
        {
            return new OneForOneStrategy(d=> Directive.Resume, false);
        }

        protected override void PreRestart(Exception reason, object message)
        {
            Console.Write(" restarting (string counter) " + reason.Message);
            base.PreRestart(reason, message);
        }


        private int _total;

        protected override void OnReceive(object message)
        {
            if (message is int num)
            {
                _total += num;
                Console.Write($" {_total} ");
            }

            if (message is string[] messages)
            {
                foreach (var msg in messages)
                {
                    var actor = Context.ActorOf<StringLengthCounter>();
                    actor.Tell(msg);
                }
            }
        }
    }

    
    public class StringLengthCounter : UntypedActor
    {
        private static int _cnt = 0;
        protected override void OnReceive(object message)
        {
            if (message is string text)
            {
                if (++_cnt > 2)
                {
                    if (string.IsNullOrWhiteSpace(text)) Sender.Tell(0);
                }
                Sender.Tell(text.Length);
            }
        }
    }
}

ok.. tried the above out in akka (JVM version)

it moans because you're trying to tell a null message in your loop on line 51.

worth seeing if akka.net is the same.. I.e. an arg exception.. your ArrayCounter isn't supervised.. appart from the default..

so that could be why.