Ionic 1 admob free plugin

Hey Everyone.
I am new to ionic and working on an already built project. I am using Admob Free plugin to show ads. But the problem is, whenever I try to edit anything (e.g. worked on onesignal push notification) this plugin breaks and stop showing any ads.
Now it’s not showing the banner and interstitial ad on app load. But it’s loading the ad as I can see in the android studio logcat. When I click on a button to show interstitial ad, it works.
All the things were working before the edit. And there was not a major change in onesignal too. just added a variable to check if the notification was clicked or not.