diff --git a/samples/grpc/iot-service-scala/src/main/resources/persistence.conf b/samples/grpc/iot-service-scala/src/main/resources/persistence.conf
index c83f56ae5..d67f12817 100644
--- a/samples/grpc/iot-service-scala/src/main/resources/persistence.conf
+++ b/samples/grpc/iot-service-scala/src/main/resources/persistence.conf
@@ -23,6 +23,10 @@ akka {
         password = ${?DB_PASSWORD}
       }
     }
+
+    # Edge may omit sequence numbers, e.g. due to compaction.
+    # Such gaps will be handled as filtered events.
+    typed.event-writer.fill-sequence-number-gaps = on
   }
 
   projection.r2dbc {