App Rejected for External Registration Feature

Good afternoon, everyone!

I received a notification that my app was rejected for the following reason: "We noticed that the user is taken to the default web browser to sign in or register for an account, which provides a poor user experience."

The app is a directory of partners that offer a benefit to our members. So the intent of the app is for users that are already registered with our nonprofit to access their benefits using existing account credentials. (Note: The sign-in itself is handled within the app after the account is created.)

Is there any way to make this compliant with guidelines without having to offer a duplicate registration form within the app and sync them?

App Rejected for External Registration Feature
 
 
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