i Boonyarit,
Thanks for contacting us. I understand that you recently made an accidental purchase from the iTunes Store.
I know where you are coming from, I too myself have actually made a few accidental purchases on my account in the past, I'm a bit of a accident prone.I'll be more then happy to review your case and see what options we have to resolve this issue in the best possible way.
I’ve reviewed your case and am issuing you a full refund for the unintentional purchase.
Within ten business days, 349.00 should be posted to the payment method used to make the purchase.