Doesn't need fixing because the response of the website indicates that there is something wrong with the database that holds your account details. That is what needs fixing and the VM staff here will arrange that as soon as they reach this thread. That will take about a week. In the meantime be patient and don't post again because thet will put you to the back of the queue for attention. We understand how frustrating this is.
As a Very Insightful Person, I'm here to share my knowledge. I don't work for Virgin Media.