Hi Angel!
Thanks for purchasing the book. I am sorry to hear about the problem. Since you purchased it on LeanPub, we need to get in touch with them to figure out the problem. Could you please send me an email (sandeep@hashnode.com) writing the issue in brief? I'll forward it to the LeanPub team and help sort it out. I am sure it's a temporary glitch and LeanPub will be able to help us out. :)