 
   if (timeStatus() == timeNotSet)
   {
+    Serial.println("get ntp time");
     setSyncProvider(getNtpTime);
-    delay(200);
+    delay(500);
   }
 
   // mqtt connect

  root["type"] = "message";
  root["id"] = nextCmdId++;
  root["channel"] = SLACK_CHANNEL;
  //root["text"] = "Hello world";
  root["text"] = "테스트 시작";
  String json;
  root.printTo(json);
  webSocket.sendTXT(json);

  while (udp.parsePacket() > 0) ;
  sendNTPpacket(mqtt_server);
  uint32_t beginWait = millis();
  while (millis() - beginWait < 2500)
  {
    int size = udp.parsePacket();
    if (size >= NTP_PACKET_SIZE)
