You have 30 days from the date of purchase to return the items that you bought. If you return the items within the 30 day period, you will be refunded 100% of the purchase price as long as you have the original receipt. If you don't have the receipt, chances are that they will refund the total amount via gift card, etc.
Go in the store. Most likely they will give you a gift card without the receipt. If you have receipt they will refund you.
They will take it back without a reciept but will give you the price that they are now. If you gave your email address they can also look it up in their system.
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