Offering rewards for reviews, only prompting happy users, or using the In-App Review API incorrectly are all policy violations. Google has seen every trick and enforces this hard.
What Apple said
“Our review team has determined that your app violates the Ratings and Reviews policy. Your app appears to solicit ratings using incentives, direct users to rate only after positive interactions in a way that manipulates the rating average, or use the In-App Review API in a manner inconsistent with our guidelines.”
Google Play's ratings need to reflect genuine user experiences. Offering coins, features, or any benefit in exchange for a review is prohibited. Only prompting users you've identified as satisfied (through sentiment detection) to skew ratings positively is prohibited. The In-App Review API has specific rules about how often and when you can call it.
While you're at it — Apple also requires these pages for every app.
Fix this rejection, then make sure you're covered on the compliance side too. Apple requires every app to link to a hosted Privacy Policy, Terms of Service, Support page, and Data Deletion page. No link means another rejection — just for a different reason.