instrumentation not connected

[wrtgj]

I set up kamon according to the guide https://kamon.io/docs/latest/guides/installation/akka-http/ with kamon 2.7.5, then I can access http://localhost:5266/, but I found that "instrumentation not connected" and I can't monitoring actor's information.
my environment is akka play 2.9.0.

here is my instrumentation setting.
kamon {
environment.service = "Ree Application"
apm.api-key = "95oc1v1dt3ruqdu4cqnjctp68o"

}
kamon.instrumentation.akka.filters {
actors.track {
includes = [ "application/" ]
excludes = [ ]
}
dispatchers {
includes = [ "" ]
}

routers {
includes = [ "**" ]
}
}
actors.doomsday-wildcard = on\

addSbtPlugin("io.kamon" % "sbt-kanela-runner-play-2.9" % "2.1.0")