Why is my UPROPERTY variable not updating in-game even though it compiles fine in C++?

Could be that, if the class not the instance being edited.

@JaninDerner

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

#pragma once

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

UCLASS()
class TPSCUSTOMENGINE_API ATestActor : public AActor
{
	GENERATED_BODY()

public:
	ATestActor();

	UPROPERTY(EditAnywhere, BlueprintReadWrite)
	float Speed = 100.0f;


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

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

do like this or as said place in level as instance and edit. Otherwise class default will be used from spawn.