How can I refund a pre ordered game

Um I preordered the game with a gift card but how can I exchange it with another's game?

You'll want to contact support and speak to billing then. http://support.xbox.com/contact-us

You can cancel it at http://account.microsoft.com

If you pre-ordered with a credit card or Paypal, you're not charged until within 10 days of the games release so it may not be eligible for a refund if that is the case (since you haven't actually been charged yet).

Otherwise, if you paid with funds from your Microsoft account you would need to submit a refund request. https://beta.support.xbox.com/help/...scriptions/digital-goods-subscriptions-refund

I cant refund my preordered game for some reason

You would have to get a refund and then purchase the correct game.