this is similar to other posts. I have been with virgin media for over 18 months but it has repeatedly not allowed me to register an account. I need this to be able to change my package. So am kind of stuck.
You can contact VM by text message or phone, renegotiate a new contract and ask them to set up/register your online account at the same time.
To be honest most people are unable to process a package change online as there is usually an "Oops something has gone wrong error" when trying to do this online because they either already have a discount and the systems require an extra bit of manipulation by the agents to set up any new discounts, or because the package they are on is no longer sold and again requires the extra manipulation by agents to change the package.
You could try the text messaging service. Just send a text with a description of regrade to 07533 051809. Your message will go into a queue and a representative will respond to you as soon as possible. It may take a few days.
You can also call 150 from your Virgin landline, or 0345 454 1111, options 1,1 and 4 (Changes to your package) butbest to call at 8am to avoid call queues
When you first signed up for VM you will have been given a phone password (memorable word) in your welcome letter/email, usually something along the lines of maiden name, town of birth, first school. If you don't have this, or can't remember it, then don't enter anything and an agent should pick up the call and you should be able to answer other questions to confirm you are the account holder,. this is usally along the lines of bank sort code, last bill amount etc, You can ask them to send out a memorable word password reminder through the post.
The Service you do for others is the rent you pay for your room here on Earth - Muhammad Ali