Hello,
I saw the screenshot you attached.
It seems that the page is not loaded correctly. Please make sure that you let the page load completely and then try to edit it.
If the issue still occurs then check with the default WordPress theme because these backend settings are woocommerce plugin functionality and our theme doesn’t influence.
If it works fine with the default WordPress theme then provide with admin panel login details of the website to check it myself and help you out accordingly.
Best Regards