Interstitial with video has a delay calling "onAdClosed"

Question

when closing the Interstital Ads(Inline Video) there is a 2-3 seconds delay before calling onAdDismissedFullScreenContent method. This bug affects only Inline Video ads. Other interstitial formats (Text, image, and rich media) work fine without delay but when an Interstitial Inline Video ad is dismissed/closed there's a delay of about 2-3 seconds to call onAdDismissedFullScreenContent. Plsss help me, :( :( :(

below is my code:

Implement Interstital Ads:

val activity = activityWeakRef.get()!!
AdManagerInterstitialAd.load(activity,
   APP_ID_ADS_INTER,
   AdManagerAdRequest.Builder().build(),
   object : AdManagerInterstitialAdLoadCallback() {

      override fun onAdLoaded(adManagerInterstitialAd: AdManagerInterstitialAd) {
         super.onAdLoaded(adManagerInterstitialAd)
         admInterstitialAd = adManagerInterstitialAd
      }

      override fun onAdFailedToLoad(loadAdError: LoadAdError) {
         super.onAdFailedToLoad(loadAdError)
         admInterstitialAd = null
      }
   })

when show Interstial Ads:

admInterstitialAd!!.show(activityWeakRef.get()!!)
admInterstitialAd!!.fullScreenContentCallback = object : FullScreenContentCallback() {
   override fun onAdFailedToShowFullScreenContent(adError: AdError) {
      super.onAdFailedToShowFullScreenContent(adError)
   }

   override fun onAdShowedFullScreenContent() {
      super.onAdShowedFullScreenContent()
   }

   override fun onAdDismissedFullScreenContent() {
      AppLogger.d(">>>>>>>>>>>>>>> delay when call this method")
      // Do back screen
      super.onAdDismissedFullScreenContent()
   }
}