wireless communication with HC-12 Transceiver

I am trying to create two-way wireless communication between two Arduinos using HC-12 Transceiver. I’m
able to send data from transmitter to receiver, but having issues getting data from receiver to transmitter.

Below are the codes fro transmitter and receiver, please anyone take a look at code and se if there is any error.

For transmitter

#include <SoftwareSerial.h>
#define setPin 6
#define button1 2
#define button2 3
#define button3 4

SoftwareSerial HC12(10, 11); // HC-12 TX Pin, HC-12 RX Pin
byte incomingByte;
String readBuffer = “”;
int button1State = 0;
int button1Pressed = 0;
int button2State = 0;
int button2Pressed = 0;
int button3State = 0;
int button3Pressed = 0;

void setup() {
Serial.begin(9600); // Open serial port to computer
HC12.begin(9600); // Open serial port to HC12
pinMode(setPin, OUTPUT);
pinMode(button1, INPUT);
pinMode(button2, INPUT);
pinMode(button3, INPUT);
pinMode(7, OUTPUT);
pinMode(8, OUTPUT);
pinMode(9, OUTPUT);
pinMode(12,OUTPUT);

digitalWrite(setPin, HIGH); // HC-12 normal, transparent mode
}

void loop() {

// ==== If button 1 is pressed, set the MINIMUM POWER
button1State = digitalRead(button1);
if (button1State == HIGH & button1Pressed == LOW) {
button1Pressed = HIGH;
delay(20);
}
if (button1Pressed == HIGH) {
HC12.println(11);
digitalWrite(7,HIGH);

delay(100);
//Set AT Command Mode
digitalWrite(setPin, LOW); // Set HC-12 into AT Command mode
delay(100); // Wait for the HC-12 to enter AT Command mode
HC12.print(“AT+P1”); // Send AT Command to HC-12
delay(200);
while (HC12.available()) { // If HC-12 has data (the AT Command response)
Serial.write(HC12.read()); // Send the data to Serial monitor
}
Serial.println(“LOWEST POWER”);
digitalWrite(setPin, HIGH); // Exit AT Command mode
button1Pressed = LOW;

}
else{
digitalWrite(7,LOW);

}

// ==== If button 2 is pressed, set the middle POWER
button2State = digitalRead(button2);
if (button2State == HIGH & button2Pressed == LOW) {
button2Pressed = HIGH;
delay(20);
}
if (button2Pressed == HIGH) {
HC12.println(111);
digitalWrite(8,HIGH);

delay(100);
//Set AT Command Mode
digitalWrite(setPin, LOW); // Set HC-12 into AT Command mode
delay(100); // Wait for the HC-12 to enter AT Command mode
HC12.print(“AT+P5”); // Send AT Command to HC-12
delay(200);
while (HC12.available()) { // If HC-12 has data (the AT Command response)
Serial.write(HC12.read()); // Send the data to Serial monitor
}
Serial.println(“MEDIUM POWER”);
digitalWrite(setPin, HIGH); // Exit AT Command mode
button2Pressed = LOW;
}
else{
digitalWrite(8,LOW);
}

// ==== If button 3 is pressed, set the MAX POWER
button3State = digitalRead(button3);
if (button3State == HIGH & button3Pressed == LOW) {
button3Pressed = HIGH;
delay(20);
}
if (button3Pressed == HIGH) {
HC12.println(1111);

digitalWrite(9,HIGH);

delay(100);
//Set AT Command Mode
digitalWrite(setPin, LOW); // Set HC-12 into AT Command mode
delay(100); // Wait for the HC-12 to enter AT Command mode
HC12.print(“AT+P8”); // Send AT Command to HC-12
delay(200);
while (HC12.available()) { // If HC-12 has data (the AT Command response)
Serial.write(HC12.read()); // Send the data to Serial monitor
}
Serial.println(“MAXIMUM POWER”);
digitalWrite(setPin, HIGH); // Exit AT Command mode
button3Pressed = LOW;
}
else{

digitalWrite(9,LOW);
}

//delay(100);

/while (Serial.available()){
HC12.write(Serial.read());
}
/

if (HC12.available()){
int input = HC12.parseInt();

if(input == 0000){
digitalWrite (12, HIGH);
/digitalWrite(2, LOW);
digitalWrite(3, LOW);
digitalWrite(4, LOW);
/

}
}
else{
digitalWrite(12,LOW);
}
}

For receiver

#include <SoftwareSerial.h>
SoftwareSerial HC12(10, 11); // HC-12 TX Pin, HC-12 RX Pin

void setup() {
HC12.begin(9600); // Open serial port to HC12
pinMode(8,OUTPUT);
pinMode(2,OUTPUT);
}
void loop() {

delay(100);
// ==== Sending data from one HC-12 to another via the Serial Monitor
while (Serial.available()) {
HC12.write(Serial.read());
}
// === If button 1 is pressed, set channel 01
if(HC12.available() > 1){
int input = HC12.parseInt();//read serial input and convert to integer (-32,768 to 32,767)
if(input == 1111 || input == 11 || input == 111)
{
digitalWrite(8,LOW);
HC12.println(0000);
}
}
else{

digitalWrite(8,HIGH);
tone(2,2000,300);

}

}