Array function is not working [SOLVED]

It's not clear to me when the motor should be switched on. You should give a better description.

But this should give the idea how to check all sensors. If all sensors measure more than 57cm, the motor will be activated.

void Sensor_Trigger()
{
  bool isMatch = true;
  for (int sonarCnt = 0; sonarCnt < SONAR_NUM; sonarCnt++)
  {
    if (sonar[sonarCnt].ping_cm() <= 57)
    {
      isMatch = false;
    }
  }

  // if all sensors measure more than 57
  if (isMatch == true)
  {
    Motor_Driver_1_RS.backward();
    Serial.println("Motor Driver 1 L/S is ON - Forward");
    delay(500);
    Motor_Driver_1_RS.stop();
    Serial.println("Motor Driver 1 L/S is OFF");
  }
}