Dear Sir / Madam

I would like to retake the exam CCB-400. I didn't pass it in June 2015, but pass another exam CCAH in Innovative Exams.

When I tried to purchase the exam, it showed error message as "You already have an enrollment active for this item".

I couldn't find any right button or link on that page.

Then, when I tried to register an exam on Innovative Exams (sign in ready), it showed another error message as

"You are not eligible to take this exam. You can only view locations or availability.

If you would like to check location and time availability, please click "Next" again.

You are not currently eligible to take this exam or have not met all requirements to take this exam. Please speak with your exam sponsor for information about eligibility requirements for this exam . or"

I couldn't find any way to retake exam. May someone teach me how to re-register exam please? Thank you very much!