I had the same problem as you, what has helped me is not running the pub upgrade command on the console. I go to the flutter packages official (pub.dev), searched the auth and its related packages and installed them by adding their latest version under dependencies in pub.yaml file.

firebase_auth: ^5.3.3 firebase_core: ^3.8.0 firebase_storage: ^12.3.6 cloud_firestore: ^5.5.0

I hope, this would help at you end.