I am so sorry. I made a typo on the book codes and thank my reader Vanessa for letting me know! The codes are REW50 for half off and REW100 for free. I guess it stands for Read an Ebook Week (REW). I left off the W. Teach me to get in a hurry <sigh>. I have corrected it in the original blog, but am leaving this out there in case anyone comes back here to see why their code won't work.
Thanks for reading this shortie!