I got hit with this as well. I put money on 3 different Apple Gift Cards from two local 7-Eleven’s and all of them came up with the “Cannot Redeem Code” “Code entered is not valid” error messages. I called Apple Support and sent them photos of the front and back of the last Gift Card I got, the envelope that it was enclosed in and the 7-Eleven receipt. After examining the photo’s, Apple Support said some character’s were missing at the end of the Gift Card code. This is the code that begins with the letter X. There was only 12 characters instead of 16. I looked closer and I noticed that some characters at the end of the code were whited out or removed somehow. You can see the smudging at the end of the code if you tilt the card just right in some light. You can also see the same thing on the number that starts with GCA that is directly below the Gift Card code. In my case, you can even see that the characters at the end of the GCA number AND the long string of numbers beneath the bar code that is printed on the outside of the sealed envelope has been whited out as well. Is someone opening legitimate Apple Gift Cards, altering them and somehow re-sealing them and taking the money that is put on them? Sure looks that way to me.