Merge Clothing Assets Error

first look at the code:

class USkeletalMesh* UMyManager::DoMerge(USkeletalMesh* RootMesh, TArray BodyParts)
{
TArray<USkeletalMesh*> Meshes;

for (auto PartInfo : BodyParts)
{
	Meshes.Add(PartInfo.Mesh);
}

Meshes.RemoveAll([](USkeletalMesh* Mesh) -> bool {return Mesh == nullptr; });

auto Target = NewObject<USkeletalMesh>(this, NAME_None, RF_Transient, RootMesh);

TArray<FSkelMeshMergeSectionMapping> InForceSectionMapping;
FSkeletalMeshMerge merger(Target, Meshes, InForceSectionMapping, 0);

merger.DoMerge();

this->MergeClothingAssets(Meshes, Target);

return Target;

}

void UMyManager::MergeClothingAssets(const TArray& ArySkeletalMesh, USkeletalMesh* NewSkeletalMesh)
{
if (ArySkeletalMesh.Num() == 0 || NewSkeletalMesh == nullptr)
{
return;
}

NewSkeletalMesh->ClothingAssets.Reset();

TArray<UMaterialInterface*> AryMaterialCloth;
TArray<int32> AryClothAsset;
TArray<int32> AryClothSubmesh;

TArray<int32> AryIgnoreIndex;
for (int32 Index = 0; Index < ArySkeletalMesh.Num(); Index++)
{
	bool IsIgnore = false;
	for (int32 CurIgnoreIndex = 0; CurIgnoreIndex < AryIgnoreIndex.Num(); ++CurIgnoreIndex)
	{
		if (Index == CurIgnoreIndex)
		{
			IsIgnore = true;
			break;
		}
	}

	if (IsIgnore)
	{
		continue;
	}

	USkeletalMesh* CurMesh = ArySkeletalMesh[Index];
	this->ClothingAssetsIsUnique(Index, CurMesh, ArySkeletalMesh, AryIgnoreIndex);
	
	//ClothingAssets Array Merge
	for (int32 ClothAssetIndex = 0; ClothAssetIndex < CurMesh->ClothingAssets.Num(); ++ClothAssetIndex)
	{
		NewSkeletalMesh->ClothingAssets.Add(CurMesh->ClothingAssets[ClothAssetIndex]);

		//
		for (int32 LODIndex = 0; LODIndex < CurMesh->LODInfo.Num(); LODIndex++)
		{
			FSkeletalMeshResource* Resource = CurMesh->GetImportedResource();
			check(Resource->LODModels.IsValidIndex(LODIndex));

			FStaticLODModel& LODModel = Resource->LODModels[LODIndex];
			int32 NumSections = LODModel.Sections.Num();

			for (int32 SecIdx = 0; SecIdx < NumSections; SecIdx++)
			{
				uint16 MaterialIndex = LODModel.Sections[SecIdx].MaterialIndex;
				uint16 ChunkIdx = LODModel.Sections[SecIdx].ChunkIndex;

				if (LODModel.Chunks[ChunkIdx].CorrespondClothAssetIndex != INDEX_NONE)
				{
					UE_LOG(LogInit, Error, TEXT("CorrespondClothSectionIndex = %d"), LODModel.Sections[SecIdx].CorrespondClothSectionIndex);

					UMaterialInterface* Material = CurMesh->Materials[MaterialIndex].MaterialInterface;

					AryMaterialCloth.Add(Material);
					AryClothAsset.Add(ClothAssetIndex);
					AryClothSubmesh.Add(LODModel.Chunks[ChunkIdx].ClothAssetSubmeshIndex);
				}
			}
		}
	}		

}


for (int32 MaterialIndex = 0; MaterialIndex < AryMaterialCloth.Num(); ++MaterialIndex)
{
	for (int32 LODIndex = 0; LODIndex < NewSkeletalMesh->LODInfo.Num(); LODIndex++)
	{
		FSkeletalMeshResource* Resource = NewSkeletalMesh->GetImportedResource();

		if (Resource->LODModels.IsValidIndex(LODIndex))
		{
			FStaticLODModel& LODModel = Resource->LODModels[LODIndex];
			int32 NumSections = LODModel.Sections.Num();

			for (int32 SecIdx = 0; SecIdx < NumSections; SecIdx++)
			{
				uint16 CurMaterialIndex = LODModel.Sections[SecIdx].MaterialIndex;
				UMaterialInterface* CurMaterial = NewSkeletalMesh->Materials[CurMaterialIndex].MaterialInterface;

				if (CurMaterial == AryMaterialCloth[MaterialIndex])
				{
					uint16 ChunkIdx = LODModel.Sections[SecIdx].ChunkIndex;

					UE_LOG(LogInit, Error, TEXT("CorrespondClothAssetIndex = %d, set = %d ,LOD = %d,ChunkIdx = %d"), LODModel.Chunks[ChunkIdx].CorrespondClothAssetIndex,
						AryClothAsset[MaterialIndex], LODIndex, ChunkIdx);

					/*ApexClothingUtils::ImportClothingSectionFromClothingAsset(
						NewSkeletalMesh,
						LODIndex,
						SecIdx,
						AryClothAsset[MaterialIndex],
						AryClothSubmesh[MaterialIndex]
						);*/

					LODModel.Chunks[ChunkIdx].SetClothSubmeshIndex(AryClothAsset[MaterialIndex], AryClothSubmesh[MaterialIndex]);
					ApexClothingUtils::ReImportClothingSectionFromClothingAsset(NewSkeletalMesh, LODIndex, SecIdx);

				

				
				}

			}
		}
		
	}
}

when I open the editor , check the 

73246-2.jpg

,
Why the Cloth Assets is None,I sure set the CorrespondClothAssetIndex = 0,

}