Cannot complete iTunes Connect account signup

I am stuck in a loop trying to sign up an account in iTunes Connect as an author. I get as far as filling in my username and password, then entering the 6 digit code, but nothing happens. It simply reverts back to the ID field again. I have tried multiple times, on 3 different browsers, emptying their cache but with no success. I simply cannot complete what should be a relatively simple operation of using my iTunes ID to create an iTunes Connect account so I can publish my book. Frustrated does not begin to describe it!

Any suggestions, please?