package modules.counter.graphql.resolvers

import akka.actor.{Actor, ActorLogging, ActorRef}
import com.google.inject.name.Named
import javax.inject.Inject
import modules.counter.services.count.CounterActor
import modules.counter.services.count.CounterActor.{GetAmount, IncrementAndGet}

object CounterResolver {
  final val name = "CounterResolver"
}

class CounterResolver @Inject()(@Named(CounterActor.name) counterActor: ActorRef) extends Actor
  with ActorLogging {

  override def receive: Receive = {
    case amount: Int => counterActor.forward(IncrementAndGet(amount))

    case GetAmount => counterActor.forward(GetAmount)
  }
}
package modules.counter.graphql.resolvers

import akka.actor.{Actor, ActorLogging, ActorRef}
import com.google.inject.name.Named
import javax.inject.Inject
import modules.counter.services.count.CounterActor
import modules.counter.services.count.CounterActor.{GetAmount, IncrementAndGet}

object CounterResolver {
  final val name = "CounterResolver"
}

class CounterResolver @Inject()(@Named(CounterActor.name) counterActor: ActorRef) extends Actor
  with ActorLogging {

  override def receive: Receive = {
    case amount: Int =>
      counterActor.tell(IncrementAndGet(amount), sender)

    case GetAmount =>
      counterActor.tell(GetAmount, sender)
  }
}
--- 
+++ 
@@ -14,10 +14,8 @@
   with ActorLogging {
 
   override def receive: Receive = {
-    case amount: Int =>
-      counterActor.tell(IncrementAndGet(amount), sender)
+    case amount: Int => counterActor.forward(IncrementAndGet(amount))
 
-    case GetAmount =>
-      counterActor.tell(GetAmount, sender)
+    case GetAmount => counterActor.forward(GetAmount)
   }
 }
Use 'forward' instead of 'tell' in actors interaction
