Unreal Engine and Steamworks - FUniqueNetId and FCloudFileHeader

Hello! I’ve been struggling for the past day trying to figure out how to read files from the Steam Cloud. I tried exposing the code to a Blueprint Function that does that. Here’s how far I got: Unreal Engine and Steamworks - FUniqueNetId and FCloudFileHe - Pastebin.com

#pragma once
 
#include "TheDarkDayPROJECT.h"
#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "ZEROSteamworksFunctions.generated.h"
 
/**
 *
 */
 
UCLASS()
class THEDARKDAYPROJECT_API UZEROSteamworksFunctions : public UBlueprintFunctionLibrary
{
    GENERATED_BODY()
 
public:
    /* Reads Files from Steam Cloud */
    UFUNCTION(BlueprintCallable, meta = (DisplayName = "Read Files from Steam Cloud"), Category = "Steamworks Cloud")
        static void steamReadFilesFromCloud(const FUniqueNetId& UserId, TArray<FCloudFileHeader>& UserFiles);
};
 
UCLASS()
class THEDARKDAYPROJECT_API UZEROSteamworksFunctions : public UBlueprintFunctionLibrary
{
    GENERATED_BODY()
 
public:
    /* List Files from Steam Cloud */
    UFUNCTION(BlueprintCallable, meta = (DisplayName = "List Files from Steam Cloud"), Category = "Steamworks Cloud")
        static void steamListFilesFromCloud(const FUniqueNetId& UserId);
};

The problem is that the compiler gives me some errors:
Unrecognized type ‘FUniqueNetId’ - type must be a UCLASS, USTRUCT or UENUM
Unrecognized type ‘FCloudFileHeader’ - type must be a UCLASS, USTRUCT or UENUM