Amazon Lack of Suppor Post Sales

I recently purchased a Samsung active watch through Amazon, this being the very first time that I have purchased through Amazon, I pre ordered the watch before 8 March 2019, the offer on the Amazon site mentioned that the preorder will come with a free wireless charger for the watch. Upon receipt of the watch, no wireless charger was delivered. I queried Amazon’s contact center but they request a screen shot of the offer from their site as evidence as they say, else they cannot help me further. I have explained to them that their site does not show the initial offer made of which I have taken up nor did I think of making a screen shot of the order as I trusted Amazon’s systems and processes, but they insist on me providing a screen shot, surely their systems would have an audit trail of their offers but the contact center just provides apologies and asks for the same, a screen shot. Really disappointed with Amazon and their lack of traceability and ability to help, I have provided my contact number but they still do not contact me, tired of their apologees, expect more from them which really is just the basic and fair to the customer. I still await professional assistance and not just scripted support words from the contact center staff.