PERMISSION_DENIED for Firebase read rule using anonymous auth

Hello,

I’m creating my app with firebase.
I have Anonymous Auth set up and one table ‘trip’ than have a field ‘user’ that stores the trip’s creator uid.
And I created the following rules in firebase:

rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /trip/{document} {
      allow create: if request.auth.uid == request.resource.data.user;
      allow read, update, delete, list: if request.auth.uid == resource.data.user;
    }
  }
}

The create works well, but the read returns an ‘PERMISSION_DENIED’ error.
Do you see any potential error ?

Thanks,

Matthias

I got a slightly different issue which got resolved by checking the stackoverflow community. Check the answers from past issues and if not enough post your question there.