Can't get status - html

Question

I am making register/login page using nodejs but when it comes to the step it returns json when accessing the database as well as when creating a new database
here is my code
register.js
const bcrypt = require("bcryptjs");
const User = require("../model/user");
const register = async (req, res) => {
const {
username,
password: plainTextPassword,
password_confirmation: someOtherPlaintextPassword,
tel_or_email,
} = req.body;
if (!username || typeof username !== "string") {
return res.json({ status: "error", error: "Invalid username" });
}
if (!plainTextPassword || typeof someOtherPlaintextPassword !== "string") {
return res.json({ status: "error", error: "Invalid password" });
}
User.findOne({ Email: tel_or_email }, async (error, user) => {
if (error) throw error;
if (user) {
console.log(user);
return res.json({
status: "ok",
success: "email is already in use, please enter another email",
});
} else {
const password = await bcrypt.hash(plainTextPassword, 10);
const password_confirmation = await bcrypt.hash(
someOtherPlaintextPassword,
10
);
const user = new User({
Name: username,
Email: tel_or_email,
Password: password,
});
user.save((error, result) => {
if (error) throw error;
console.log(result);
});
return res.json({ status: "ok", success: "user successfully created" });
}
});
};
module.exports = register;
status work in the first return ( return res.json({ status: 'error', error: 'Invalid username'}) )and the second( return res.json({ status: 'error', error: 'Invalid password'}) ) , remaining is not