Arduino Uno and tricky text in serial monitor

Hi and Happy Christmas Holiday to everybody. Yesterday I discovered this fascinating technology for IoT. I followed thoroughly base tutorial to light an LED on my Arduino Uno USB connected to my PC. Got my authentication token via email and entered it into Arduino_Serial_USB sketch, I compiled my sketch and as I opened serial monitor, I saw things like these…and of course, project on my iPhone stays offline.

Moreover, as I start .bat script on command shell, it stays stuck on

DSR is OFF as I try connection to blynk-cloud on port 8442. (Sorry, I cannot post more than one image)

as if it did not connect to the cloud.

What shall I do? Where’s the trick?

Thank to everyone.

You should close serial monitor, as you’re trying to use the same usb cable for both debug prints and Blynk data (that you see currently). That won’t work. Both Blynk sketch and the .bat script need exclusive access to that Serial.

I close Arduino IDE, as I run the .bat , but it’s the same. I’ve not changed any cable. Anyway I’ll try connecting Uno to my PC directly without any USB hub.