Google Interstitial Ad Starting with a Blank Page

I had the banner ad in my app and added Interstitial Ad to my app. As soon as I load the app data from server on the start, I get a Blank black screen that disappears after first touch. This happens on android haven’t tried iOS.

Your displaying an ad right when your app starts?

If so, the ad probably doesn’t have time to load before being displayed. 

Have you tried other devices?

There is a button that I press to download the data and start ad engine at the same time. It does exactly the same on a Sony and a Samsung phone. This is the link to the app if you wanna try:

https://play.google.com/store/apps/details?id=com.jorc.amirfarazmand.english&hl=en

That is the case in both iOS and Android.

Your displaying an ad right when your app starts?

If so, the ad probably doesn’t have time to load before being displayed. 

Have you tried other devices?

There is a button that I press to download the data and start ad engine at the same time. It does exactly the same on a Sony and a Samsung phone. This is the link to the app if you wanna try:

https://play.google.com/store/apps/details?id=com.jorc.amirfarazmand.english&hl=en

That is the case in both iOS and Android.