Hi Auttavut,
Thanks for contacting us. I understand that you are requesting a refund for items that were purchased accidentally. I would want to look into any options available to me as well if I unintentionally purchased something, and I will be more than happy to assist you today.
After carefully reviewing your case, we’ve determined your purchase doesn't meet the conditions for a refund. If you’d like to learn more about our refund policy, see this page:
http://www.apple.com/legal/internet-services/itunes/ww
Thanks,
Jan
iTunes Store Customer Support
http://www.apple.com/support/itunes/ww
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