Staticmesh disappears

Hi, I have a problem with the Unreal Engine. I create 2 static meshes for 1 actor, it compiles without errors and both staticmesh are displayed on the class image, but when I place it as an instance of the class, the 2nd staticmesh disappears

AKost::AKost()
{
	PrimaryActorTick.bCanEverTick = true;
	bGenerateOverlapEventsDuringLevelStreaming = true;

	niz = CreateDefaultSubobject<UStaticMeshComponent>("nizKosti");
	ConstructorHelpers::FObjectFinder<UStaticMesh> bebra(TEXT("/Game/Modelki/obekti/nizKosti"));
	niz->SetStaticMesh(bebra.Object);
	niz->SetEnableGravity(false);
	niz->SetCollisionProfileName(TEXT("OverlapAll"));

	seredina = CreateDefaultSubobject<UStaticMeshComponent>("seredinaKosti");
	ConstructorHelpers::FObjectFinder<UStaticMesh> telci(TEXT("/Game/Modelki/obekti/seredinaKosti"));
	seredina->SetStaticMesh(telci.Object);
	seredina->SetEnableGravity(false);
	seredina->SetCollisionProfileName(TEXT("OverlapAll"));
	/*seredina->SetRelativeLocation(FVector(0, 0, 25));
}

image


But if you create a blueprint of this class, then the blueprint is created with 2 staticmesh
image
And if I uncomment on this passage

/*seredina->SetRelativeLocation(FVector(0, 0, 25));

Unreal engine crashed after this, as if trying to move it, but in fact it does not exist

How it works?