title: Ads are not served to my app even After integrating with MoPub
body: <p><img src="https://i.stack.imgur.com/4EH51.png" alt="enter image description here">I have created an account in Mopub and integarted neccessary code to my android app to display a banner ad. After that Demo MoPub ad started displayed.
  I think MoPub is like a mediator between publishers and ad networks? correct me if i am wrong.
  so i have created account in AdMob as well and successfully integrated it in MoPub(means added that network in MoPub). but still only MoPub Demo ads is getting displayed, what might be the problem?</p>