You have not assigned the attributes in the products. You need to create attributes, assign them to the product, and enable showing on the product page: https://woocommerce.com/document/variable-product/
Sorry to say that your given login details are not working, please share the correct login details of your site. So I will further check on your site and give you a possible solution.
Your issue has been resolved. I have removed the custom attributes (in iPhone 12 Pro Moment Case – Yellow product) and added the Global attributes it is showing fine. Check back your site and check the issue.