If I understand correctly, you purchased an iTunes gift, you received the receipt for the purchase, but you don't have the gift. If this was a gift for another person, it would email the other person with the instructions on how to redeem the gift. If they did not receive the email with the instructions, you can send it to them again.
If you sent an iTunes Gift and your recipient didn't get the email with the instructions on how to redeem it, you can resend them the gift from your iPhone, iPad, or iPod touch, Mac, or PC.
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