Only the manufacturer of a product can produce this as they are the people who have put an item through the required testing. If your product is not a Samsung then naturally Amz will not accept their declaration of conformity for a different product. Ask the manufacturer of your item.

Firstly check your paperwork some invoices are issued along with the declaration/certificate of conformity.
Try the distributor or your supplier as they may have it?
If not, some manufacturers make this available on their web site.

The Declaration of Conformity is a legal Document which must accompany all CE Marked products sold in the European Union.
This document needs to include the following:
Name and address of organisation taking responsibility for the product
Description of product
A list of the applicable safety directives the product complies with
Details of relevant standards may be included.
The manufacturer or a representation of the organisation placing the product on the market should then sign the Declaration.
You will need to double check that what you have sent does infact have all the above info mentioned on it.
Hope this helps
Tracey