Suspension why?

So I bought a digital season of Fear the Walking Dead. The code was said to be UV so I tried to redeem it. It did not work. I messaged the seller and waited a bit recieved no responce. I sent atleast 4 or 5 in total and 5 days later once Ive sent all the pics and did everything Gameflip wants then this guy messages me.

He claims he never got alerts or emails that his items had bee. Sold but he was respo ding to people on his items during the time i bought it.

He then tells me its a different site to redeem the code but it was to late the refund was underway. In the end i get suspended. Ive never misused anything from anyone and ive always had good interactions with people here. So whats the deal?