I have this function:

    app.post('/create-checkout-session', async (req, res) => {
   
    const priceId = req.body.PRICE_ID;
    console.log(priceId)

const session = await stripe.checkout.sessions.create({
  mode: 'subscription',
  payment_method_types: ['card'],
  line_items: [
    {
      price: priceId,
      // For metered billing, do not pass quantity
      quantity: 1,
    },
  ],
  // {CHECKOUT_SESSION_ID} is a string literal; do not change it!
  // the actual Session ID is returned in the query parameter when your customer
  // is redirected to the success page.
  success_url: 'http://localhost:6166/?session_id={CHECKOUT_SESSION_ID}',
  cancel_url: 'http://localhost:6166/test',
});

// Redirect to the URL returned on the Checkout Session.
// With express, you can redirect with:
//   res.redirect(303, session.url);

})

and when I log the priceId, it logs it, so I know my front-end is hitting the function, however, it is just HANGING, it won't redirect, and it won't give me any console errors. Any ideas what I'm doing wrong?