Never received E-gift card as promised

So I bought this Sony XBR65X850F TV from dell. When I placed the order I was following a promo link that says the purchase includes a $400 e-gift card, which will be sent to my email account within 20 days from shipping. The order was placed on 8/21 and I waited till 9/12 and still got nothing so I contacted dell support. Over the past several weeks I have been exchanging emails with dell employee Allan Jones and Syed Zaidi. Originally my support request number was 979662301 but somehow during the emails there has been another support request number 980634593 showed up on the email's subject. In the emails dell employee Syed Zaidi said he checked and found no record of my order associated with any promotions. However even though I didn't take a screenshot at the time I placed the order, I found the same product from dell on some deal-sharing websites, with the date of posting very close to the time I placed the order. The deal-sharing websites points to an expired dell promotion page: https://deals.dell.com/compare/1aha. This page contains the same exact details as the promotion info I saw when I placed my order. Please investigate this issue. My order number is and my dell purchase ID is 2006891097508.