If you're receiving error even if everything in Firebase appears to be in order, try this

So, I've been getting errors in Firebase recently, despite the fact that everything I did was correct. The mistake was then found to be due to a compatibility issue with the most recent version of Firebase.

As a result, instead of importing firebase from firebase/app I now import it from firebase/compat/app I performed the same thing with firestore and auth. My problem is solved simply by adding the /compat path.

I hope this information is useful to you at some time.