This app does not work!

So I purchased ACLS and BLS to review on my iPad and I cannot even access them!!! First the app wouldnt recognize my username and password then it finally did (and, yes I was entering the correct information) and now that it has it wont open the books, it keeps saying delete and Download again, which I have done about 20 times and it still doesnt work. PLEASE FIX SO I CAN USE THE BOOKS TO REVIEW FOR MY COURSES!!!!!

Katiewatey about AHA eBook Reader, v5.0.1