The reason why you are receiving messages with “[TEST]” in the subject line to your Sent Messages page is because one or more of your messages is still set to the status of "Test”. This means that those particular messages will be triggered by real order events but will be visible only on the Sent Messages page under Communications in your left navigation, NOT to your customers.
You can confirm these messages are not sent to your customers by viewing the "Sent" page in your Amazon Seller Central account. To do this, login to your Amazon Seller Central account, navigate to the "Messages" page (link in top left), then click on the "Sent" tab. From this page, you can confirm that your Test messages are not sending to your customers.
Please keep in mind that there are two types of test messages:
Messages that you save and send to your test email (ie. When you click on “Save & Send Test”): the Communications Center does not have a real customer order from which to pull in details. When sending the test message, we populate the order details with fictitious content, including a fake Order Id, product, etc. So do not be alarmed when your email variables populate with words like “Test” or links containing “TEST-ORDER-ID”, etc. (Click here to read more about links in test messages.)
Messages the Communications Center generates: To test the actual content of a message sent to a buyer, leave the message in Test Mode until it generates a test message for you. Once you receive a new order, any messages in Test Mode will send a message. This message will only be seen in the Sent Messages tab under Communications in your left navigation, with a subject line that starts with "[TEST]". Please keep in mind that these messages will not be sent to your email address.
This can be alarming at first because you will see Test messages with Order IDs. Essentially, this is the Communications Center's way of saying you had an order that qualified for your message, and if the message was Active, it would have been sent to your customer. However, because the message is in Test mode, only a Test message was generated. Because these type of test messages are based off real order events, they do contain real order information.
If you would like to change the status of your message, or would like to begin sending messages to customers, you can change the status to "Active" by following these directions:
From the Automated Messages page, under Communications in your left navigation, find the message you want to activate. Where you see the name of that message, navigate to the far right side of that row under "Status". To set your message to "Active", click on the dropdown and select "Active". You should see messages begin sending within 24 hours.