Need help with ir receiver

hello i quite new to this i recently want to use a ir remote for an automated curtain rail and using a code i found online but the IR receiver didnt detect anything an error message came when compling it IRrecv: :decode(decode_results) i dont know what to do. can anyone explain to me what the problem is

#include <IRremote.h>
#include <DS3231.h>
#include <LiquidCrystal.h>
#include <Stepper.h>
#include <EEPROM.h>

const long int OpenCurtain = 0xFF02FD; //button for opening the curtain
const long int CloseCurtain = 0xFF22DD; //button for closing the curtain
const long int OpenAlarmScreen = 0xFF906F; //button for opening the alarm screen to be able to set the alarm
const long int EnterButton = 0xFFC23D; //button for confirming the value written in the alarm screen
const long int add1 = 0xFFA857; //button to add 1 to the number displayed in the alarm screen
const long int subtract1 = 0xFFE01F; //button to subtract 1 from the number displayed in the alarm screen

const int stepsPerRevolution = 200;  // change this to fit the number of steps per revolution
// for your motor

int curtainDistance = 1000; //IMPORTANT: whatever value you write here, will decide how far your curtains open, so be VERY careful not to put
//a very high value in, as the curtains might open too much and you DEFINITELY don't want that. Better start of with a small value.

//Uncomment the following lines (the curtainTogglestate ones) and then upload the code. Make sure that your curtains are closed. 
//After you've uploaded the code, 
//the arduino will save these values to its EEPROM and update them whenever you open or close the curtains. It's very important 
//to comment these lines back after you've uploaded the code. You do this by adding // in front of your line like I've done on this line.

//int curtainTogglestate = 0; //the curtains are closed
//int curtainTogglestate2 = 1; //the curtains are closed

// initialize the stepper library on pins 8 through 11:
Stepper myStepper(stepsPerRevolution, 7, 8, 9, 11);

int stepCount = 0;  // number of steps the motor has taken

byte alarm[8] = {
  B00000,
  B00100,
  B01110,
  B01110,
  B01110,
  B11111,
  B00100,  
  B00000,
 };
 
DS3231  rtc(SDA, SCL);

LiquidCrystal lcd(3, 4, 5, 6, 12, 13); // Creates an LC object. Parameters: (rs, enable, d4, d5, d6, d7) 

const int RECV_PIN = 2;

bool AlarmClock = false;

// Define IR Receiver and Results Objects
IRrecv irrecv(RECV_PIN);
decode_results results;
Time t;

int OnHour = 9; //these are the values for your alarm, but don't worry, these are just default values. You'll set your alarm using the remote. 
int OnMin = 00; //(24 HOUR FORMAT)

int Enter = 0;
int state = 0;

int address = 0;
int address2 = 1;

void setup(){
  // Enable the IR Receiver
  irrecv.enableIRIn();

  rtc.begin(); // Initialize the rtc object
  lcd.begin(16,2); // Initializes the interface to the LCD screen, and specifies the dimensions (width and height) of the display } 
  lcd.createChar(7, alarm);

  //The following lines can be uncommented to set the date and time. You have to do this once, upload and then comment them back again
  //rtc.setDOW(WEDNESDAY);     // Set Day-of-Week to SUNDAY
  //rtc.setTime(22, 13, 00);     // Set the time to 22:13:00 (24hr format)
  //rtc.setDate(5, 8, 2020);   // Set the date to August 5th, 2020

  myStepper.setSpeed(300); //set the speed of the stepper motor to 300. You can change this value. For me, 300 was about the maximum value

  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(11, OUTPUT);

  digitalWrite(7,LOW);
  digitalWrite(8,LOW);
  digitalWrite(9,LOW);
  digitalWrite(11,LOW); 

  lcd.display();

  Serial.begin(9600); //If your lcd is acting weird, comment this line because it might help. This line is only necessary for reading the IR transmitter codes
}
 
void loop(){
 
int curtainTogglestate = EEPROM.read(address); //read the curtainTogglestate from the EEPROM. It checks whether the curtains are closed or opened.
int curtainTogglestate2 = EEPROM.read(address2);

 lcd.setCursor(0,0);
 lcd.print("Time:  ");
 lcd.print(rtc.getTimeStr());
 
 lcd.setCursor(0,1);
 if(AlarmClock == true){
  lcd.write(7);

 }

 lcd.setCursor(6,1);
 lcd.print(rtc.getDateStr());


t = rtc.getTime();
     
    
 if(t.hour == OnHour && t.min == OnMin && AlarmClock == true){
     lcd.clear();
     lcd.setCursor(0,0);
     lcd.print("WAKE UP, LAZY!");
     
     if(curtainTogglestate==0 && curtainTogglestate2==1){
          
          curtainTogglestate=1;
          curtainTogglestate2=0;
          while(stepCount < curtainDistance) {
            myStepper.step(stepsPerRevolution / 100);
            stepCount++;
           
          }

            digitalWrite(7,LOW);
            digitalWrite(8,LOW);
            digitalWrite(9,LOW);
            digitalWrite(11,LOW); 
            delay(1000);
            stepCount = 0;
            AlarmClock = false;
       
        }
    lcd.clear();
    }
  

  if (irrecv.decode(&results)){
    // Print Code in HEX
    Serial.println(results.value, HEX); //this line is only necessary for reading the IR transmitter codes (in the Serial monitor). You can comment it afterwards    

        switch(results.value){
          case OpenCurtain:
               
          if(curtainTogglestate==0 && curtainTogglestate2==1){
          
          curtainTogglestate=1;
          curtainTogglestate2=0;
               lcd.clear();
               lcd.setCursor(0,0);
               lcd.print("curtain open"); 
          while(stepCount < curtainDistance) {
            myStepper.step(stepsPerRevolution / 100);
            stepCount++;
           
          }

          
            digitalWrite(7,LOW);
            digitalWrite(8,LOW);
            digitalWrite(9,LOW);
            digitalWrite(11,LOW); 
            delay(1000);
            stepCount = 0;
            lcd.clear();
        }  
        break;

        case CloseCurtain: 
        if(curtainTogglestate==1 && curtainTogglestate2==0){
          
          curtainTogglestate=0;
          curtainTogglestate2=1;
               lcd.clear();
               lcd.setCursor(0,0);
               lcd.print("curtain close"); 
          while(stepCount < curtainDistance) {
            myStepper.step(-stepsPerRevolution / 100);
            stepCount++;
           
          }

            digitalWrite(7,LOW);
            digitalWrite(8,LOW);
            digitalWrite(9,LOW);
            digitalWrite(11,LOW); 
            delay(1000);
            stepCount = 0;
            lcd.clear();
       
        }
        break;

        case OpenAlarmScreen: 

        lcd.clear();
            lcd.setCursor(0,0);
            lcd.print("Alarm: ");
            lcd.setCursor(7,0);
            lcd.print(OnHour);
            lcd.print(":");
            lcd.print(OnMin);
 
            lcd.setCursor(7,0);
            lcd.blink();

        do {
          
          if (irrecv.decode(&results)){

            switch(results.value){
            case EnterButton: 
            Enter = 1;
            lcd.setCursor(10,0);
            break;

            case add1:
            OnHour = OnHour + 1;
            lcd.setCursor(0,0);
            lcd.print("Alarm: ");
            lcd.setCursor(7,0);
            lcd.print(OnHour);
            lcd.print(":");
            lcd.print(OnMin);
 
            lcd.setCursor(7,0);
            lcd.blink();

            break;

            case subtract1:
            OnHour = OnHour - 1;
            lcd.setCursor(0,0);
            lcd.print("Alarm: ");
            lcd.setCursor(7,0);
            lcd.print(OnHour);
            lcd.print(":");
            lcd.print(OnMin);
 
            lcd.setCursor(7,0);
            lcd.blink();
            break;
            
            }
            irrecv.resume();
            }
        } while(Enter == 0);

        while(Enter == 1) {
          if (irrecv.decode(&results)){

            switch(results.value){
            case EnterButton: 
            Enter = 2;
            AlarmClock = true;
            break;

            case add1:
            OnMin = OnMin + 1;
            lcd.setCursor(0,0);
            lcd.print("Alarm: ");
            lcd.setCursor(7,0);
            lcd.print(OnHour);
            lcd.print(":");
            lcd.print(OnMin);
 
            lcd.setCursor(10,0);
            lcd.blink();

            break;

            case subtract1:
            OnMin = OnMin - 1;
            lcd.setCursor(0,0);
            lcd.print("Alarm: ");
            lcd.setCursor(7,0);
            lcd.print(OnHour);
            lcd.print(":");
            lcd.print(OnMin);
 
            lcd.setCursor(10,0);
            lcd.blink();
            break;
            
            }
            irrecv.resume();
            }
        }
        Enter = 0;
 
        break;
        
        }
        
        irrecv.resume();
  }
  EEPROM.update(address, curtainTogglestate);
  EEPROM.update(address2, curtainTogglestate2);
} 

Post the error messages.

The IRremote library was changed this year so that now two incompatible versions exist. Get the other library version or code for your actual version. Run the library examples to verify that the library itself is okay.

Your post was MOVED to its current location as it is more suitable.