WooCommerce checkout page isn’t working

I have exhausted all online resources on this and have not found any solution. Here’s the scenario:

Go to https://schwartzfineminerals.com/shop/ you can add products to the cart and successfully view the cart page – BUT when you click “Proceed to Checkout” it briefly shows the checkout page and then flips to a white screen with my client’s account email in the top left corner and the browser continues to load with no completion.

PLEASE HELP! I have tried absolutely everything I can think of – all plugins are up to date, I’ve disabled plugins, switched the theme, recreated the woocommerce pages. NOTHING is working.

Thank you in advance!

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