Can not link PaperSprite to PaperSpriteComponent

I just want to link sprite to paperSpriteComponent and keep getting this 3 errors:

1.Use of undeclared identifier ‘ConstructorHelpers’;
2.Member reference base type ‘const wchar_t [28]’ is not a structure or union;
3.‘UPaperSprite’ does not refer to a value;

 // Fill out your copyright notice on the Description page of Project Settings.
    
    #include "Skybox.h"
    #include "PaperSpriteComponent.h"
    #include "PaperSprite.h"
    
    // Sets default values
    ASkybox::ASkybox()
    {
        // Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
        PrimaryActorTick.bCanEverTick = false;
        
        if(!RootComponent) {
            RootComponent = CreateDefaultSubobject<USceneComponent>(TEXT("SkyboxBase"));
        }
        
        SkyboxSprite = CreateDefaultSubobject<UPaperSpriteComponent>(TEXT("SkyboxSprite"));
        SkyboxSprite->SetupAttachment(RootComponent);
        // this line gives errors without it project compiles just fine
        SkyboxSprite->SetSprite(ConstructorHelpers::FObjectFinder<UPaperSprite>(TEXT("/Game/Sprites/Skybox_Sprite")).Object);
    }
    
    // Called when the game starts or when spawned
    void ASkybox::BeginPlay()
    {
        Super::BeginPlay();
        
    }
    
    // Called every frame
    void ASkybox::Tick(float DeltaTime)
    {
        Super::Tick(DeltaTime);
        
    }

I am out of ideas. I’ve tried to make it work all day, but keep getting the same error.

Try to include:

#include "UObject/ConstructorHelpers.h"

Omg. you are my Hero! How do people know this things? I’ve spent hours… :frowning: