[SOLVED] Device offline (UNO using USB-link)

New progress
I have runned the following code and it run successfully

//#define BLYNK_PRINT SwSerial  // ONLY AVAILABLE IF YOU HAVE A USB2TTL

//#include <SoftwareSerial.h>  // ONLY AVAILABLE IF YOU HAVE A USB2TTL
//SoftwareSerial SwSerial(10, 11); // RX, TX  ONLY AVAILABLE IF YOU HAVE A USB2TTL
    
#include <BlynkSimpleStream.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "xxxxxxxxxxxx";

BlynkTimer timer;

// This function sends Arduino's up time every second to Virtual Pin (5).
// In the app, Widget's reading frequency should be set to PUSH. This means
// that you define how often to send data to Blynk App.
void myTimerEvent()
{
  // You can send any value at any time.
  // Please don't send more that 10 values per second.
  if(analogRead(A1>0))
     Blynk.virtualWrite(V5, 255);
  else
    Blynk.virtualWrite(V5,0);
}

void setup()
{
  // Debug console ONLY AVAILABLE IF YOU HAVE A USB2TTL
  //SwSerial.begin(9600);

  // Blynk will work through Serial
  // Do not read or write this serial manually in your sketch
  Serial.begin(9600);
  Blynk.begin(Serial, auth);

  // Setup a function to be called every second
  timer.setInterval(1000L, myTimerEvent);
}

void loop()
{
  Blynk.run();
  timer.run(); // Initiates BlynkTimer
}
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