EMG Sensor to control servo not working

Hey guys, i got a Grove EMG Sensor attached to the Grove shield on pin A0, however the value in the serial plotter is not changing when I flex my muscles and therefor can't move the servo motor...

Anyone knows why? Here is my code:

#include <Servo.h>

//Threshold for servo motor control with muscle sensor. 
//You can set a threshold according to the maximum and minimum values of the muscle sensor.
#define THRESHOLD 250

//Pin number where the sensor is connected. (Analog 0)
#define EMG_PIN 0

//Pin number where the servo motor is connected. (Digital PWM 3)
#define SERVO_PIN 3

//Define Servo motor
Servo SERVO_1;

/*-------------------------------- void setup ------------------------------------------------*/

void setup(){
  
  //BAUDRATE set to 115200, remember it to set monitor serial properly. 
  //Used this Baud Rate and "NL&CR" option to visualize the values correctly.
  Serial.begin(115200);
  
  //Set servo motor to digital pin 3
  SERVO_1.attach(SERVO_PIN);
  
}
  
/*--------------------------------  void loop  ------------------------------------------------*/

void loop(){

  //The "Value" variable reads the value from the analog pin to which the sensor is connected.
  int value = analogRead(EMG_PIN);

  //If the sensor value is GREATER than the THRESHOLD, the servo motor will turn to 170 degrees.
  if(value > THRESHOLD){
    SERVO_1.write(170);
  }

  //If the sensor is LESS than the THRESHOLD, the servo motor will turn to 10 degrees.
  else{
    SERVO_1.write(10);
  }

  //You can use serial monitor to set THRESHOLD properly, comparing the values shown when you open and close your hand.
  Serial.println(value);
}

Thanks in advance

Is the wiring correct?
Sorry, i never used EMG sensor before, but i found this page.

  if(value > THRESHOLD)
  {
    SERVO_1.write(170);
  }

  //If the sensor is LESS than the THRESHOLD, the servo motor will turn to 10 degrees.
  else
  {
    SERVO_1.write(10);
  }

  //You can use serial monitor to set THRESHOLD properly, comparing the values shown when you open and close your hand.
  Serial.println(value);
}
if(value > THRESHOLD)

*Remake this TRESHOLD into new value setup.