Is there have a way to offline authenticate android application with using MongoDB Realm?

Question

I want to make an android APP that can be used totally without internet. currently, I'm using MongoDB Realm service with MongoDB Atlas as a database. I'm having a problem application can't log in without the internet. once it is log in with the internet it is working fine when there's a connection. But I need to connect the Realm database even with offline. once connection established all data need to sync with the server. this application going to work in a rural area when there's no connection.