If your app lets users create an account, they must be able to delete it from within the app — and that deletion must remove their data too. This became a hard requirement in 2023 and Google enforces it at review.
What Apple said
“Your app allows users to create an account but does not provide an option to request account deletion from within the app. As of Google Play's updated policy, apps that allow users to create accounts must also provide a way to delete those accounts. Please add an account deletion option before resubmitting.”
Google, like Apple, now requires that if you let users create accounts, you let them delete those accounts from inside the app. This means a clearly accessible menu option that triggers account deletion, and the deletion must actually remove user data — or at minimum, begin the deletion process with clear communication to the user about what happens and when.
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.