C++ error when compiling an Actor class (trying to create a function for spawning an actor)

Yes of course, here my code:
My .h file




// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "MyActorTest.generated.h"


UCLASS()
class MYPROJECT2_API AMyActorTest : public AActor
{
    GENERATED_BODY()

public:    
    // Sets default values for this actor's properties
    AMyActorTest();

protected:
    // Called when the game starts or when spawned
    virtual void BeginPlay() override;

public:    
    // Called every frame
    virtual void Tick(float DeltaTime) override;

    UFUNCTION(BlueprintCallable, Category = "Spawning Actor")
    AMyActorTest* AMyActorTest::SpawnObjectActor(AActor * ActorReference, UClass * ClassReference, FVector Location, FRotator Rotation);

};



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And my cpp file:




// Fill out your copyright notice in the Description page of Project Settings.

#include "MyProject2.h"
#include "Engine/Level.h"
#include "MyActorTest.h"


// Sets default values
AMyActorTest::AMyActorTest()
{
     // Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
    PrimaryActorTick.bCanEverTick = true;

}

// Called when the game starts or when spawned
void AMyActorTest::BeginPlay()
{
    Super::BeginPlay();

}

// Called every frame
void AMyActorTest::Tick(float DeltaTime)
{
    Super::Tick(DeltaTime);

}

AMyActorTest* AMyActorTest::SpawnObjectActor(AMyActorTest * ActorReference, UClass * ClassReference, FVector Location, FRotator Rotation) {

UWorld* const World = ActorReference->GetWorld();
//AMyActorTest * MySpawnedActor = TSubclassOf<AActor> MyObject;
AMyActorTest * MySpawnedActor = ActorReference;
AMyActorTest * ActorTest = new AMyActorTest();

    if (World != NULL)
    {
        World->SpawnActor<AMyActorTest>(Location, Rotation);
    }

    return MySpawnedActor;
}



https://forums.unrealengine.com/filedata/fetch?type=thumb&filedataid=116744

Thanks for your help, i hope i will resolve my problem ^^