Ionic Native Admob Free not show ads after app download from store android

My app not show ads after upload on play store(Android) and installed on device. The strange thing is that if I use the same signed package and install it via “adb install” command, the ads works. My app is approved inn store and connect in admob page. I’ve connect app today.

let RewardVideoConfig: AdMobFreeRewardVideoConfig = {
  isTesting: false,
  autoShow: true,
  id: id
};
this.admobFree.rewardVideo.config(RewardVideoConfig);
this.admobFree.rewardVideo.prepare().then(() => {
}).catch(e => alert(e));

Someone has already happened or knows the reason? Thanks!