Amazon has a Buyer-Seller Messaging Service that allows buyers and sellers to communicate in the Amazon marketplace via email addresses which are masked to the users. You can use the facility to reply to messages from people you are either buying from or selling to.
Reply via your email
Find messages from buyers in your email inbox. They will show as being received from an encrypted Amazon email address. This will look something like firstname.lastname@example.org.
Click “Reply” to respond to the buyer’s message and hit “Send.” Check your sent messages folder on the Buyer-Seller messages page for confirmation that the message is received by Amazon. Sometimes there will be delays from your own email provider preventing the message instantly reaching Amazon.
Be aware of the Amazon terms and conditions about using this service. Your email should be a reply to the query only. It should not include links to any other website, contain seller logos or contain marketing or promotional material.
Reply via your seller account
Check the “Received Messages” tab on your Amazon Buyer-Seller Messages page. Find the message you want to reply to and click the link of the buyer’s message to reply. You can use the “Filter by” drop-down menu to search by dates.
Type in your message in the "reply" text box and click on the "reply" button. Then look in your “Sent Messages” tab to check that your message has been forwarded to the buyer.
Add attachments by clicking on the "add attachments" button. You must use either .txt, .pdf, .jpg, .gif, ,png or Word documents to a maximum of 10MB. Only Microsoft Office Word documents up to 2003 will be accepted.
You can also block or approve email address of senders using the Alternate Address page on your Amazon account.