Can't get Doom Dark Ages Promo Code after purchasing Asus Rog Strix Monitor

[AwesomeLife]

Hi, I am new here, so apologies if I am writing this in the wrong place!
I have bought:
27'' ASUS ROG Strix XG27ACDNG
Ordered on 16th of May.
The receipt is from 20th of May.
I received it on 21th of May.
(I can attach any necessary documents needed)

Local Bulgarian Store I purchased it from:
https://ardes.bg/product/27-asus-rog-strix-xg27acdng-90lm0an0-b01970-461179

I tried claiming a code through here:
https://www.asus.com/my/events/register/activity_8847

Upon entering the Serial number of my monitor I get a pop up that says:
The 90 number 90LM0AN0-B01970 of the serial number entered is not eligible for this event even tho my serial number is nothing like this. (its 6 letters followed by 6 numbers without any space in between)

I have also checked multiple places and I see everywhere that this monitor is part of the Doom Dark Ages Campaign and I would be very happy if its possible to get a code for the game somehow.

[Hankenstein]

Did the store you bought it from have the event? Did it say the game inclouded in the screen you bought? Otherwise its gonna be hard.