user doc ID doesn't match the firebase auth users UID - React Native Expo

[ryanbakker]

When a new user is sent to the firestore database, I want the doc ID of the user to match the users UID in firebase auth. Currently the document is being assigned a random ID. The user's data is being sent to the db in the following useEffect:

React.useEffect(() => {
    checkLocalUser();
    const unsub = onAuthStateChanged(auth, async (user) => {
      if (user) {
        await AsyncStorage.setItem("@user", JSON.stringify(user));
        setUserInfo(user);

        // Check if the user already exists in Firestore
        const usersRef = collection(db, "users");
        const q = query(usersRef, where("userId", "==", user.uid));
        const querySnapshot = await getDocs(q);

        if (querySnapshot.size === 0) {
          // User does not exist, add them to Firestore
          await addDoc(usersRef, {
            displayName: user.displayName,
            photoURL: user.photoURL,
            email: user.email,
            userId: user.uid,
            coverPhoto: "",
            bio: "",
          });

          console.log("New User => ", user.displayName, user.uid);
        } else {
          console.log("User already exists:", user.displayName, user.uid);
        }
      } else {
        console.log("User not authenticated");
      }
    });

    return () => unsub();
  }, []);