Cannot Log in more than one user with expo google auth/ firebase

I am using ```

to authenticate and log-in to my app. When I am logged in tho it seems another user cannot log in. 

Below is the code I am using to accomplish can I have more than one user logged in simultaneously or is it a bug in my code? Does the user have to be signed out before another user can?

First Sign in with google async:

async function signInWithGoogleAsync() {
const result = await Google.logInAsync({
androidClientId: CLIENT_ID,
iosClientId: CLIENT_ID,
scopes: [

if (result.type === "success") {
  return result.accessToken;
} else {
  return { cancelled: true };


Then on success from sign in with google async...sign in to firebase with credentials.

function onSignIn(googleUser, firebaseUser) {
// We need to register an Observer on Firebase Auth to make sure auth is initialized.
let unsubscribe = firebase
.onAuthStateChanged(async (firebaseUser) => {
try {
// Check if we are already signed-in Firebase with the correct user.
if (!isUserEqual(googleUser, firebaseUser)) {
// Build Firebase credential with the Google ID token.
// console.log(“GOOGLE USER ID TOKEN”, googleUser);
const credential = firebase.auth.GoogleAuthProvider.credential(

        // Sign in with credential from the Google user.
        const result = await firebase
        await db.collection("users").doc(result.user.uid).set({
          profile_picture: result.additionalUserInfo.profile.picture,
          first_name: result.additionalUserInfo.profile.given_name,
          last_name: result.additionalUserInfo.profile.family_name,
          access_token: googleUser.accessToken,

        console.log("RESULT USER ID", result.user.uid);
        //Retreive Calendars from the user using the UserId Returned
        await getCalendarsFromUser(result.user.uid);
        //Navigate to next page upon logging in and passing user data to Redux Store

      } else {
        console.log("User already signed-in Firebase.");
    } catch (error) {
      // Handle Errors here.
      let errorCode = error.code;
      let errorMessage = error.message;
      // The email of the user's account used.
      let email =;
      // The firebase.auth.AuthCredential type that was used.
      let credential = error.credential;
      console.log(errorCode, errorMessage, email);