For those if you have the same issue as well, I found how to fix:
const unsubscribeClosed = rewarded.addAdEventListener(
AdEventType.CLOSED,
() => {
rewarded.load();
Alert.alert("Tebrikler!", "Reklamı izleyerek ödül kazandın.");
}
);
This is going to trigger when user closes the ad. It will load the new ad and when you press the button to watch a new ad, it is going to open without any problem. I found it on github account of the "react-native-google-mobile-ads". There are more evens on AdEventType and others. Here you can find all:
https://github.com/invertase/react-native-google-mobile-ads/blob/main/src/ads/RewardedAd.ts
And the documentation of "React Native Google Mobile Ads"
https://docs.page/invertase/react-native-google-mobile-ads/displaying-ads