CORS Error Firebase Cloud Functions in React Contact Form

Question

I have a react contact form, with a firebase cloud function handling sending an email with nodemailer and an axios post request to store the data in my firestore db. I am using CORS in my function, but am still getting the CORS error in my console when submitting the form.

Access to XMLHttpRequest at 'https://.cloudfunctions.net/submit' from origin 'http://localhost:3000' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. I've spent about 2 hours googling and from what I've read it seems that if I have const cors = require('cors')({origin: true}); it should work. Any assistance would be great.

const functions = require('firebase-functions');
const nodemailer = require('nodemailer');
const cors = require('cors')({origin: true});
const gmailEmail = functions.config().gmail.email;
const gmailPassword = functions.config().gmail.password;

const mailTransport = nodemailer.createTransport({
  service: 'gmail',
  auth: {
    user: gmailEmail,
    pass: gmailPassword,
  },
});

exports.submit = functions.https.onRequest((req, res) => {
  cors(req, res, () => {
    if (req.method !== 'POST') {
      return;
    }
    const mailOptions = {
      from: req.body.email,
      replyTo: req.body.email,
      to: gmailEmail,
      subject: `${req.body.name} submitted a quote request!`,
      text: req.body.message,
      html: `<p>{req.body.message}</p>`,
    };
    mailTransport.sendMail(mailOptions).then(() => {
      console.log('New email sent to:', gmailEmail);
      res.status(200).send({ isEmailSend: true });
      return;
    });
  });
});


// This snippet is in my contact.js component
const sendEmail = () => {
    axios
      .post(
        'https://<myurl>.cloudfunctions.net/submit',
        formData
      )
      .then((res) => {
        db.collection('emails').add({
          name: formData.name,
          email: formData.email,
          phone: formData.phone,
          message: formData.message,
          time: new Date(),
        });
      })
      .catch((err) => {
        console.log(err);
      });
  };

Answer 1

I deleted the cloud function and recreated it and I no longer had the cors issue.