I'm stuck in the bluetooth serial communication at starterkit tutorial

Hello, support team.
I'm eager to make it communicate via bluetooth dongle.
However, it seems there is problem on this line as below.
-------------------------------(from fakeBluno example)----------------
void setup() {
Serial.begin(115200); // initialize serial communication

BLESerial.setName("Bluno101");
BLESerial.begin();
//Serial.println("Bluetooth device active, waiting for connections...");
while(!BLESerial);
}
-------------------------------(below ommitted)-----------------------

please I need help.
I don't know why the procedure is looped forever at the while statement.
BLESerial doesn't seem to be true even if I connected the usb dongle.

I also tried to upgrade the firmware as here, https://www.dfrobot.com/wiki/index.php/ ... n.EF.BC.89

But, it also failed saying time-out message.
I am really stuck on this point.
Please help me.
sincerely
from your big fan customer.