Firebase JS无法在身份验证后添加姓氏

Question

Im working with react-native redux app. This is my newly created firebase database.

Everything is working fine, user is able to sign in and Sign-Up as well. But I have this little code after sign-up I'm trying .set({ firstname, lastname }) firstname, lastname which does not reflect in database. (github repo: https://github.com/steelx/react-native-redux-app )

    export const signUpUser = ({ firstname = "", lastname = "", email, password }) => (dispatch) => {
    dispatch({ type: SIGN_UP_REQUEST });

    firebase.auth().createUserWithEmailAndPassword(email, password)
        .then((user) => {

            // const currentUser = firebase.auth().currentUser;
            // currentUser.updateProfile({
            //     displayName: `${firstname} ${lastname}`,
            //     THIS WORKS
            // })

            firebase.database().ref('users/' + user.uid)
            // THIS DOES NOT WORK
                .set({ "firstname": 'AJINKYA', "lastname": 'AJINKYA' })
                .then(() => {
                    dispatch({ type: SIGN_UP_SUCCESS, payload: user });
                    Actions.home();
                });
        })
        .catch((error) => { dispatch({ type: SIGN_UP_FAILURE, payload: authFailMessage(error.code) }); });
};

Firebase rules

{
  "rules": {
    "users": {
      "$uid": {
        ".read": "auth != null",
        ".write": "auth != null && auth.uid == $uid"
      }
    }
  }
}

Answer 1

Sorry my bad I was passing uid as undefined at ref. and originally before posting this question the RULES were set to Locked.

and my rules were also wrong. Later I updated rules to => as a quick fix I added these rules. Everything works fine now.

{
  "rules": {
    ".read": "auth != null",
    ".write": "auth != null"
  }
}