This tool, located under Promotion on your Publisher Hub, is used to easily view and reply to customer reviews and discussion comments. When any customer leaves a written comment or review it will appear on the Reply To page where you can easily respond. View the product page to see the full comment thread.
Anyone with access to your Publisher account will be able to view and reply to these comments. Their comments will be visible on Replies in the tool, however you will NOT see other replies on Discussion comments.
The first reply to a review or comment is shown, view the full product page to see the replies from other customers.
Remember, it’s not always the best course of action to reply to a customer leaving comments or reviews that you may feel are not in good faith, or what you want to hear, but it’s always better to treat everyone with respect and courtesy in a public forum, as your other customers will always be watching.