Having got the problem solved I should probably give an update.
So bear in mind my login and password was always correct naturally one is nonplussed when your login and password is rejected and you are then told to click on the "I am not a robot" button and then select multiple images of shopfronts or traffic lights...screen after screen. This I did but frankly by the 4th or 5th screen I just aborted - well why wouldn't I, I'm already thinking something is broken and I'm not stuck in an endless security loop.
Thankfully the second line line support guy who I got through to after 2 hours of phone calls did persevere and to whom I had given my login and password and hey presto it actually worked.
Ok, so you could blame my stupidity for not keeping going buy I think there are two issues here and I could be excused for what happened.
1) Clearly Virgin had not fully tested the "user experience". I don't know quite why the "I am not a robot" security layer was so over zealous. I think 2 screens max should have been what I was displayed with not half a dozen. One could also ask the question. If my login and password was correct why the heck was it rejected in the first place and why was I subjected to this idiotic security protocol.
2) This scenario was clearly not in the first line support playbook. But then again if they had tested the user experience out as per #1 then it would have been.
So the next time on any app you get asked to identify all the squares with a shop front etc.....just keep going...and going....and going....and just maybe the application will let you in.
Fraser
PS At least it is gratifying that Rose_B who seems to work for Virgin is monitoring the forum and private messaged me in an effort to resolve. Next time though...just make sure the application is tested from the user point of view.