Is this the Retailer where you purchased your Rzyen: https://www.computeruniverse.net/en/amd-ryzen-7-3700x-boxed-inkl-wraith-prism-kuehler
If it is, it does seem to be participating in the AMD Promotion:
If this Retailer is participating in the AMD Promotion, THEY MUST GIVE YOU THE GAME COUPON OR CODE for you to be able to redeem it at AMD REWARDS site.
Once Computer Universe sends you the Game Coupon or Code, you go to AMD REWARDS (GAME REDEMPTION PORTAL - AMD Rewards ) and input the code. AMD will have you download a small verifying program to make sure you have a qualified AMD product INSTALLED on your computer. Once it is verified then it will give you instructions on how to redeem your games.
I have attached the AMD Terms & Conditions ( Ryzen Equipped to Win Game Bundle – COMPONENT, SI & OEM ) that explains everything about the AMD Promotion and how to redeem it to get your games.
Just click on the attachment to download and open the PDF file.
Make sure you purchased the Ryzen within the Time Frame of the AMD Promotion according to AMD Terms & Conditions and redeem it before the final expiration date.
