Unfortunately you can't and if you try through support they might change it, but most likely many of the participants already own the game and it probably would take way too long for the support to get back to you.
Your best bet is just to delete this one and create a new giveaway for the correct game.
If this is from Dollar Viva Bundle, then you have a wrong game.
This is the correct one: http://store.steampowered.com/app/344810/Total_Extreme_Wrestling/
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can i change it now? (the giveaway)
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Unfortunately you can't and if you try through support they might change it, but most likely many of the participants already own the game and it probably would take way too long for the support to get back to you.
Your best bet is just to delete this one and create a new giveaway for the correct game.
Comment has been collapsed.