2Visitors cannot add anything to the shopping cart – shopping cart remains empty

Hello .,
the following problem: I am building a fresh WooCommerce. The problem is that as a pure visitor, you can not add products to the cart. The shopping cart is always empty. Only if you are logged in as a user (user role no matter admin, customer, etc.) – the main thing is that you are logged in. Have also once forwarded to the cart after the add to cart => same problem. The shopping cart remains empty.

It’s a very fresh setup without me making any changes anywhere in the code.

WooCommerce Version 5.1.0
I already disabled all plugins (except WP and WOO) => same error.
There is no error in the Console.
WooCommerce Status:
WooCommerce REST API package: 5.1.0
WooCommerce Blocks package: 4.4.3
Action Planner Package: 3.1.6
WooCommerce Admin Package: 2.0.2
WordPress memory limit: 256 MB
PHP version: 7.4.14
WP Theme Flatsome (current version).

I have already test disabled all plugins (Except WooCommerce) and switched to the default theme 2020 .

I have tested all browsers (Chrome, FF, Edge, Opera) , 2 different computers, 3 different smartphone (Apple + Android) -> Everywhere the same problem.

The PHP Error Log does not log any errors (related to the shopping cart) .

In the console also no error is logged.

Only in the debug file something was logged.

This message was triggered by wp-debugging.

Call stack:

wp_die()
wp-content/plugins/wp-debugging/vendor/norcross/debug-quick-look/includes/parser.php:54
DebugQuickLook\P\run_parse()
wp-content/plugins/wp-debugging/vendor/norcross/debug-quick-look/includes/actions.php:59
DebugQuickLook\A\run_quicklook_action()
wp-includes/class-wp-hook.php:292
do_action('admin_init')
wp-admin/admin.php:175

Does anyone know what this could be?

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