First, please verify that the code is enter exactly as it appear. The code is case sensitive. Also, verify that the "0" and "O" or "I" and "l" are entered as the right letter or number. For iBooks, it is not uncommon that the code did redeem, but failed to complete the download process. If you are redeeming an iBook please see the Apple FAQ's for more specific support. If you still have trouble please submit a support ticket on shelfit.com, and one of our agents will get this resolved for you.