How to handle timescale when using admob?

I am using google admob rewarded interstitial ads and before showing/closing the ad timescale is set to 0 but as soon as I click on close ad button it sets the timescale back to 1 itself.

ADMob automatically sets the timescale to 0 when showing an ad, so that the game doesn’t run in the background. If you want the timescale to be continued with value 0 after you close the ad, you can implement the AdClose Handle:

this.rewardedAd.OnAdClosed += HandleRewardedAdClosed;

and in the method you set your timescale to 0

public void HandleRewardedAdClosed(object sender, EventArgs args)
    {
        Time.timeScale = 0;
    }

I know this is an old post but I have a similar issue on Unity 6 with Google Mobile Ads 10.3.0. The OnAdClosed event handler does not exist in this case. The OnAdFullScreenContentClosed event handler is the last one to fire before the time scale is set back to 1. I even see a “Resume Game” information message in the console (clearly from Google Mobile Ads). In my case, I have the game paused before the advert is shown and then have a count down after the advert before the game must start, but Google Mobile Ads sets time scale to 1 before my count down is over. Very annoying as I have no way to fix this at the moment!