In my booking workflow, I have the confirm reservation button going to the cart. The Cart page shows no products in it when making booking an accommodation.
I have WooCommerce as my Payments Gateway. I have a Reservations product set up in WooCommerce.
You should make sure you have a WooCommerce Checkout page with the [woocommerce_checkout] shortcode in it created and selected next to the corresponding option under WooCommerce ->Settings ->Advanced: https://prnt.sc/ullsfm.