Ionic AdMobPro onAdPresent issue

Hello everyone

I use Ionic Admob Pro plugin
https://ionicframework.com/docs/native/admob-pro/

I have subscriber to onAdPresent event which fires when user finishes watching video.
And in my admob account I have configured rewardType = ‘coins’ and rewardAmount = 2

onAdPresent works fine, but sometimes after watching video illegal values passed to this subscribe.
Sometimes my configured values are passed, but sometimes passed rewartType=‘reward’ and rewardAmount=1

I guess it some default values of rewarded videos, but why these values are passed for my configured admob account?

> ngOnInit() {
>     this.subscription = this.admob.onAdPresent().subscribe(res => {
>       if (res.adType == "rewardvideo" && res.rewardType == "coins" && res.rewardAmount == 2) {
>         //SOMETIMES THIS BLOCK IS NOT EXECUTED BECAUSE OF res.rewartType has some other value instead of my configured
>       }
>   }
> 
>   showRewardedVideo() {
>     this.admob.prepareRewardVideoAd({
>       adId: 'ca-app-pub-****',
>       autoShow: true
>     });
>   }

Can anybody help?