Sending NOTIFY to SmartApp not working

Receiving simple GET, POST, PUT requests inside SmartApp works fine, however, when trying to use NOTIFY method (which is required for proper SSDP implementation) is not working for me

mappings {
  path("/notify") {
    action: [
      NOTIFY: "handleNotification"
    ]
  }
}

def handleNotification() {
	log.debug "Got notification ${params}"
    
}

handleNotification method is not being called when sending NOTIFY request to the hub.
What to do? How to handle such requests.

BTW, when sending the same request to the device it is being handled properly inside parse() method, which looks like “catch-all” style one.

Ideas?