Adding empty Gameplay Tag to a USTRUCT

Header:

#pragma once

#include "CoreMinimal.h"
#include "GameplayTagContainer.h"
#include "StatTagValues.generated.h"


USTRUCT(BlueprintType)
struct FStatTagValues
{
	GENERATED_BODY()

		UPROPERTY(EditAnywhere, BlueprintReadWrite)
		bool Testbool;

	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		float TestFloat;

	UPROPERTY(EditAnywhere, BlueprintReadWrite)
		//FVector testtag;
		FGameplayTag testtag;


	FStatTagValues()
	{
		Testbool = false;
		TestFloat = 0.0;
		testtag = FGameplayTag::EmptyTag;
		//testtag = FVector::ZeroVector;
	}
};

I am a total noob when it comes to unreal c++. But what I am missing here? It will compile just fine if I set testtag to be a vector.

I found the source of the error: I did not have the module “GameplayTags” listed in PublicDependencyModuleNames in the Build.cs file for my project.