When you receive an order, you can initiate communication with the buyer using the Contact Buyer form.
When a message is sent with the Contact Buyer form, a copy will be sent to your Customer Service email address located on your Seller Account Information page. The email the buyer receives will include an anonymized email address to which the buyer can respond directly. All subsequent communications will occur directly through email or in the Buyer-Seller Messages inbox of your seller account.
See Customer Communication Guideline for details of customer communication guideline.