Cannot access to the e-book

I brought both wiley plus registration code and textbook. I also have a course code for the registration. I could access to the e-book on the wiley plus at the first day I regeistered, but I could not afterward. I tried several times, but I could not access to the e-book. When I click the course link on the wiley plus, only the window shows that this page cannot be displayed. So, I tried it on the other browers, mozilla and chrome, but, it still does not work. what is wrong with this web site?

In addition, i cannot find the answer and solutions for the textbook problem in this web site. The contents of the texbook shows that you can find the solution on this web site, but I cannot find them