Securing firebase realtime database when using only anonymous login

问题

I am using firebase realtime database with firebase anonymous login.

When I use the below private rules to secure the firebase realtime database. I get Permission denied error on my client when an anonymously logged in user tries to save data to firebase realtime database. How can I get over this error ?

Note: I don't want to use public rules and I want to use firebase anonymous login.

Private rules: Firebase realtime database rules that allows only authenticated users to read and write data.

// These rules grant access to a node matching the authenticated
// user's ID from the Firebase auth token
{
  "rules": {
    "users": {
      "$uid": {
        ".read": "$uid === auth.uid",
        ".write": "$uid === auth.uid"
      }
    }
  }
}

Public rules: Firebase realtime database rules which give anyone, even people who are not users of your app, to read and write access to database

// These rules give anyone, even people who are not users of your app,
// read and write access to your database
{
  "rules": {
    ".read": true,
    ".write": true
  }
}

来源：https://stackoverflow.com/questions/61116549/securing-firebase-realtime-database-when-using-only-anonymous-login