We need you to edit your item Layout, so it has a wrapper/holder for the Ads.
Keep in mind this wrapper/holder could be expanded or contracted, so make sure your layout adapts to this changes look into adaptive layouts for this, this size changes in the layout will be limited by the ad configurations that the infinite scroll is using, these can be edited in the code on manual initialization, or in our dashboard in case of auto and single tag initialization.

This is because we can not edit your data for adding new items to the adapter, so we take the existing item views and add the ads to them. You can customize which items have ads when you create the configuration for the infinite scroll.