Hi @enzka007,
I’ve been working on this issue myself with my own published app-- that is taking some time on my end and I do apologize. Because Admob is a third party integration, we also have to investigate if the issue lies with that third party.
At this point, there is a likelihood that there is no bug on our end. The reason there is only one interstitial ad being shown could be due a multitude of factors, all beyond our control as a platform. Keep in mind that there is no guarantee of an ad always being placed on your app just because you add an interstitial ad in Thunkable.
Ad inventory, demand, and fill rate can all vary due to downloads, impressions, reviews, invalid activity, or active users.
Although it’s a few years old, our Admob Troubleshooting Guide still has lots of good advice and shows some best practices for using Admob ads.
I’ll have more information this week. Again, thanks for your patience as we’re investigating this.