Please help me on turning the game open

Unity Engine
,
1

My idea is that when the user downloads and opens it for the first time, i will set a variable such as OpenCounting = 0 , after the user finishes playing and closes the game and comes back, then open counting >= 1 will always appear ads. So and so on, but when i code, it always jumps to Debug.Log("------------------------Fail to load ads ") , did i write anything wrong?

using UnityEngine;

public class GameManger : MonoBehaviour
private int OpenCounting = 0;

{
private void Awake()
{
checkOpenScene();
{
private void checkOpenScene()
{

if (timeOpenScene++ == 1)
{
IronSourceManager.instance.ShowInter(IronSourceManager.instance.callBackInterComplete, IronSourceManager.instance.callBackInterFaild);
Debug.Log("--------------------Open Count " + timeOpenScene);
}
else
Debug.Log("------------------------Fail to load ads ");
}
{
2

at least need to save the variable somewhere, like playerprefs (so that it keeps the value between runs)