title: AdMob stop showing banner after removing the mediation - Android
body: <p>I had Smart Banner and normal banner in my app.
  they were working normally, i tried to add mediation with AdColony, i made all the good integration.
  After the AdColony Network was always pending optimazation, I decided to remove the mediation.</p>
  <p>when the mediation was removed and now the AdMob (default) is only present.
  The Banners stopped showing any ads.</p>
  <p>what could went wrong??</p>