How do I resolve an issue with a missing letter on an Apple Gift Card?

The link you want is here, and you should follow the steps for when the code is unreadable.

If you can't redeem your Apple Gift Card, App Store Card, or App Store & iTunes Gift Card - Apple Support

If your Apple Gift Card is missing a letter, please contact Apple Support or visit an Apple Store with your receipt. They can verify the issue and help resolve it.

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