thank you, good idea.... so I've tried Chrome, Microsoft Edge and Firefox (that I was using already). I can get to the page on chrome and edge, but sign in either fails or says this is a sub account, sign in with your main account, even though it is definitely the main account address I'm using.
I've tried using the log in details on the main virginmedia site and it is definitely the main account I'm using. I've also check there's no extra spaces at the end or beginning of the email address.
Originally I managed to sign in the day the new box arrived, but the settings didn't copy across even though it said they had. I did read here that we were not along in having the issue. I thought I'd leave it a week and then try again, but can't even log in now.