diff --git a/index.js b/index.js
index 5621cc4..38e6870 100644
--- a/index.js
+++ b/index.js
@@ -86,6 +86,13 @@ bot.getMe().then(function (me) {
 bot.on('text', function (msg) {
 	logger.info('Incoming message for ' + botUsername + ' (' + msg.chat.id + '): ' + msg.text, {message: msg});
 
+    if (!msg.from.username) {
+        var replyMessage = "Pesan anda diabaikan, anda belum memiliki username pada telegram: " + msg.text;
+		logger.info(replyMessage, {msg: msg});
+        bot.sendMessage(msg.chat.id, replyMessage);
+		return;
+    }
+
     var from = msg.from.username.toUpperCase() + config.msisdn_suffix;
     updateChatId(from, msg.chat.id);