Why won’t an array pass with axios.post?

I’m trying to pass an array with ids to a backend in node.js. When console.log(Products) run before the axios.post(), the Products array has two ids in it. When I console.log(req.body.products) in my backend, the array is empty. How can I still access the array in my backend?

Frontend code

const Products = []

                        tempProd.forEach((item) => {
                            firebase.firestore().collection('products').where('name', '==', item.name).get().then((querySnapshot) => {
                                querySnapshot.forEach((doc) => {
                                    Products.push({
                                        price: doc.data().priceID,
                                    })
                                })
                            })
                        })

                        console.log(Products)

                            axios.post('https://Kvam-E-sport-API.olsendaniel04.repl.co/invoice', {
                                products: Products,
                                cus_id: response.data.medlem.id,
                            }).then((response) => {
                                console.log(response)
                            })

Backend code

app.post('/invoice', cors(), async (req, res) => {
      console.log(req.body)
      subscription = await stripe.subscriptions.create({
        collection_method: 'send_invoice',
        customer: req.body.cus_id,
        items: req.body.products,
        days_until_due: 14,
      })

    res.json({
      subscription: subscription
    })
  })