There is a solution. Put your phone on computer cause you can have access to delete and create new files if you do it via your PC or laptop even if it's not rooted. Delete com.android.vending folder (/storage/emulated/0/.jm/com.android.vending) and create a txt the same name without extension. So create a com.android.vending.txt and then delete it's extension. Now the pop up windows ads will disappear.