Hello,
If I understand correctly, you are here because you were writing the reviews under the apps you were using and the review didn't show up? If that's the case we can't help you because this is developer forum support.
However, since I'm developing apps for Apple App Store and I'm also a user of apps that other developers make and also leave reviews to them, I'm pretty certain that the developers themselves can't block or delete any reviews that the user leaves under their app. It is possible that the developer can delete ratings but this can only be done when updating the app and all ratings are gone, however last time I checked the reviews (comments) can't be removed.
Maybe it is possible that you are using bad language while reviewing the app and the review system blocks your review. Additionally, the review system sometimes deletes reviews if it determines they are "fraudulent" or generally inappropriate.
Best