Checkout page not working and getting cart empty issue after product added to ca

We have implemented Woo Payments and woocommerce B2B plugin in my website and after the setup plugin, we added the product to the cart with the B2B wholesaler User, and then proceed to checkout it gives the cart is empty error.

Product URL: https://clientszone.net/clients/818solution/product/420-grade-stainless-steel-single-edge-razor-blade/

Process of duplicate issue

1. https://prnt.sc/1d9Kc_wX3pyd
2. https://prnt.sc/gFLThXjSmyb6

We have used Woo Payments for payment with express checkout, so if we disable the express checkout option in payment it works fine, If we enable the express checkout option with guest user product options it works fine, it looks like something is conflicting with WooCommerce B2B plugin and WooPayment(express checkout option).

Please let me know how to resolve this issue.

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