Is it forbidden to change the giveaway gift by agreeing with the winner?

not its not allowed

Contact support and dont mark it as recived

It is forbidden. The creator must give you at least what's indicated on the giveaway. Period.

Anything not being that could get BOTH of you suspended.

Having said that I hope you reach an agreement, and don't bother for your English, it's quite good. :)

You should mark it as unreceived and contact Support.

I don't think that's allowed. The giveaway creator should give you the Steam key for the game. If not, then it should be marked as not received.

let me switch it around.. Other person gives you the different gift, you mark it as recieved .. Now fast forward a month down the road.. You post something on this form that draws lurkers attention and they look in see YOU didnt activate YOUR winnings. You tell your story but at this point no one will believe you. You are now a vile person because you traded or sold your gift you got from SG ... see where Im going

It's against SG rules to do that.

Ask the person to buy you the game on Steam, or don't take the key and mark as not received.

I recommend making the gifter get the game advertised on Steam and giving it to you.

thanks for your replies :) I got it now