in Woocommerce checkout page, shipping cost not updated when changing payment type, But shipping cost changes when updating address fields.

i have set new custom stock status in woocommerce as:

I have created a user role called wholesaler which allows me to separate my normal clients with our partners. Is there a way to display the user role somewhere in the WooCommerce order in the Wordpress admin panel? So whenever I open the order I can easily see if the user is wholesaler or normal customer.

I am trying to modify order line sub/totals after order submit using the hook 'woocommerce_checkout_create_order_line_item'. I can change the values, and they show up correctly in the order email, but the order total doesn’t update.

Would anyone have an example of a woocommerce checkout validation, where I can fail the validation, if they have already purchased 2 products in the last 30 days?

I am trying to add a wholesale price on my Variable products but I wonder if I can keep the same field as for my simple products. The code I have for my simple products is this: