Samsung — Offer/scheme not honoured

I am Ishan Kakkar, a Samsung customer. I purchased a Samsung Frame TV LS03A 55 inches in april 2022. Through my student advantage account I was provided an offer of free bezel. The coupon code provided never worked due to the fault of the Samsung website and I was never able to get the free bezel. Even after raising the complaint more than 9 times and even writing to the service head, the service team replied that since the coupon coun not be applied in that month the offer is no longer valid. Whose fault is that the website wont let me apply the coupon code?

The customer service kept on sending me coupon codes but no one bothered to check why the website wont let me allow applying the coupon. I even went ahead to tell them that there was a bug in their website but no one would listen.

For a bug in their website why am I the one suffering?
The ticket id for this incident is 52184499.
The free bezel offer and screenshot is attached.
I even raised the complaint with the service head on the 6th of June 2022.
Its about to be an year since my purchase yet samsung won't own up to its responsibility.