Motor not moving together (Human following Robot)

I'm using an Arduino UNO R3 and on top I have a motor shield R3. I'm only using two motors but when I upload the code only one motor works for both the right and the left. I have the ultrasonic sensor connected to A0 and A1 and the ultrasonic sensor in A2 and A3.

I'm using a pack of 3 AA batteries. The two motors are in the A channel and B channel.

Preformatted text

#include<NewPing.h>
#include<Servo.h>
#include<AFMotor.h>
#define RIGHT A2
#define LEFT A3
#define TRIGGER_PIN A1
#define ECHO_PIN A0
#define MAX_DISTANCE 100
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE);
AF_DCMotor Motor1(1,MOTOR12_1KHZ);
AF_DCMotor Motor2(2,MOTOR12_1KHZ);

Servo myservo;
int pos =0;
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
myservo.attach(10);
{
for(pos = 90; pos <= 180; pos += 1){
myservo.write(pos);
delay(15);
} for(pos = 180; pos >= 0; pos-= 1) {
myservo.write(pos);
delay(15);
}for(pos = 0; pos<=90; pos += 1) {
myservo.write(pos);
delay(15);
}
}
pinMode(RIGHT, INPUT);
pinMode(LEFT, INPUT);
}
void loop() {
// put your main code here, to run repeatedly:
delay(50);
unsigned int distance = sonar.ping_cm();
Serial.print("distance");
Serial.println(distance);
int Right_Value = digitalRead(RIGHT);
int Left_Value = digitalRead(LEFT);
Serial.print("RIGHT");
Serial.println(Right_Value);
Serial.print("LEFT");
Serial.println(Left_Value);
if((Right_Value==1) && (distance>=10 && distance<=30)&&(Left_Value==1)){
Motor1.setSpeed(120);
Motor1.run(FORWARD);
Motor2.setSpeed(120);
Motor2.run(FORWARD);

}else if((Right_Value==0) && (Left_Value==1)) {
Motor1.setSpeed(200);
Motor1.run(FORWARD);
Motor2.setSpeed(100);
Motor2.run(BACKWARD);

}else if((Right_Value==1)&&(Left_Value==0)) {
Motor1.setSpeed(100);
Motor1.run(BACKWARD);
Motor2.setSpeed(200);
Motor2.run(FORWARD);

}else if((Right_Value==1)&&(Left_Value==1)) {
Motor1.setSpeed(0);
Motor1.run(RELEASE);
Motor2.setSpeed(0);
Motor2.run(RELEASE);

}else if(distance > 1 && distance < 10) {
Motor1.setSpeed(0);
Motor1.run(RELEASE);
Motor2.setSpeed(0);
Motor2.run(RELEASE);

}
}

It looks like you tried to post your code using code tags but failed. Please follow the instructions in How to get the best out of this forum

The Arduino Motor Shield R3 uses A0 and A1 for measuring the current through the two motors. You should pick other pins for your ultrasonic sensor.

My guess is that the adafruit "AFMotor.h" library may not be directly compatible with the Arduino Motor Shield R3.