Marketing directly to the Amazon customers can be a violation of the policies & agreements of Amazon. The basic of the Amazon requirement state is that a seller will not be using Amazon information contact or market it to a customer with the mission of making additional or some kind of alternative purchases outside of the Amazon like directly on the personal website. One can certainly have the logo and name and even mention the website address in the email address that you use or in the invoice on the items that are shipped from the dropship wholesale distributor but Amazon will really want to make it sure that a person is not really trying to list a few items coming at a steep discounts and then going for the communication part directly without involving the Amazon and convincing some of them to shop on the personal website instead on Amazon.
What not to follow regarding email to save Amazon account suspension?
You can mention your email address, invoice but sharing your reference of the domain and not directly asking the customer to stop purchasing products from Amazon because on the personal website I am offering a variety of products coming all at once with better rates than Amazon. This is a really basic thing that you will have to avoid at every point and saving your amazon account suspension from happening anytime in near future of your online selling.
The violation of any Amazon policy for restricted items or prohibited contents. This is often a section that can really bring up many issues especially if you are a new seller who is new to suppliers and the product itself. For like most of the product categories it is not really a great issue but with the adult products and health-related items the potential violations are really common and one can really get to face it once.
An inventory source has it already filtered out any of the known issues that have been reported by the other sellers for a person but as in case of new items there is a change in policies and some are even added, a person wants to remain aware so one can actually use the InventorySource.com which is an accounting tool that filters to reduce any potential issue that is in the product.