sorry, but that's not how the site works.

"When should I mark a gift I won as "Received" or "Not Received"?

You should only mark a gift as "Received" when you have both (i) received the exact game described in the giveaway, and (ii) activated that game on the Steam account you used during registration. In all other instances you should mark the gift as "Not Received" one week after the giveaway has ended." 

I can't mark this as received, you made a mistake.