Automatic tollbooth

#include <SoftwareSerial.h> //header file of software serial port
#include <Servo.h>
SoftwareSerial Serial1(2, 3); //green:RX, white:TX in order
Servo myservo;
void setup()
{
  Serial.begin(9600); //set bit rate of serial port connecting Arduino with computer
  Serial1.begin(115200); //set bit rate of serial port connecting LiDAR with Arduino
  myservo.attach(8);
  myservo.write(0);
}

bool open;

void loop()
{
  int d = distance();
  if (d < 30)
  {
    myservo.write(70); // if the distance is lesser than 20, then open the tollbooth
    open = true;

  }
  else if (open == true) {
    delay(1500);
    myservo.write(0);
    open = false;
  }

}

// calculating the distance
int distance()
{
  int uart[9];
  const int HEADER = 0x59;

  if (Serial1.available())
  {
    if (Serial1.read() == HEADER)
    {
      uart[0] = HEADER;
      if (Serial1.read() == HEADER)
      {
        uart[1] = HEADER;
        for (int i = 2; i < 9; i++)
        { //save data in array
          uart[i] = Serial1.read();
        }
        int check = uart[0] + uart[1] + uart[2] + uart[3] + uart[4] + uart[5] + uart[6] + uart[7];
        if (uart[8] == (check & 0xff))
        {
          int dist = uart[2] + uart[3] * 256; //calculate distance value

          return dist;
        }
      }
    }
  }
}