Admob ad will not load. Error 2. It worked before but suddenly stopped

Question

Here is the entire class that I am trying to load a banner ad into (createAd() method does the work)

public class HomeActivity extends Activity {

    privat         


        

Answer 1

Another issue could be an adblocker application as suggested in this post: https://stackoverflow.com/a/36010639/3596576 by @Durian.

For me this was the issue.