When a buyer files a Claim under Amazon’s A-to-z Guarantee, you will receive an email notifying you of the Claim. You can also track Claims filed by your buyers by navigating to the A-to-z Guarantee Claims page in Your Seller Account under Performance tab. Email notifications are sent for your convenience only.
https://sellercentral.amazon.com/gp/help/external/27951?language=en-US