Won Bundle but got only one game from bundle. What to do?

whatever you decide to do, don't mark as received if you didn't get everything you won

What was the bundle?

Contact the creator and ask about it. If he doesn't provide the second game of the bundle, mark es "not received."

Just out of curiosity, what was the bundle?

Contact the creator of the giveaway (can be done through the giveaway, just write a comment), and inform them that you only got one game. They'll have to provide you a key for the missing game.

If you didn't get everything you were supposed to get, you should try contacting the creator first and explain the situation.

If the creator doesn't respond, you should mark it as "not received" after 7 days.

Contact the creator first and give him the opportunity to correct the problem. By the way, was one of the games in the bundle free? Because it isn't unheard of for people to make a giveaway for a bundle when they can't see the game they have a key for in the list...

As other ppl said, don't mark as received if you didn't receive all that it says in the bundle, because marking as received will only give you problems for not activating won games, so yeah as other ppl said contact the creator and explain him the situation. If he doesn't provide the missing games then mark as not received after 7 days.

Thx a lot, those suggestions were also my preferred course of action.
Bundle was Haegemonia ( http://store.steampowered.com/sub/43429/ ) but only received a key for Haegemonia: Legions of Iron…

Haegemonia: Legions of Iron is one of the free game from the microids card thing i believe