Works OK for me with Chrome and Firefox but not my preferred Opera (each to their own eh )
Comes up with an error in Cloudfare screen print below. Is this an browser problem or a NSC host problem
I presume that you have tried removing the NSC cookies from Opera?
I had exactly the same issue, but only with Chrome. Removed the NSC cookies, was back in (although had to reset my password, as I had forgotten it).