Diameter iRules attachment?

I'm creating iRules for a Diameter message routing virtual server.

I can't seem to get the events DIAMETER_INGRESS or DIAMETER_EGRESS to be executed by the irule.

I have the following simple iRule but but I get no log messages in /var/log/ltm when requests are sent.

when DIAMETER_INGRESS {
  log local0. "diameter ingress event detected"
  if {[DIAMETER::command] == 268} {
    log local0. "diameter eap request detected"
  
  }
}


when DIAMETER_EGRESS {
  log local0. "diameter egress event detected"
  if {[DIAMETER::command] == 268} {
    log local0. "diameter eap egress detected"
  
  }  
}
}

I've attached this iRule to the transport profile as well as the VS but no log messages.

The message routing configuration is working fine I get a request from upstream which F5 sends downstream and a response is back upstream.

What am I doing wrong?