Can you login to "My VM" with your VMO2ID user and access your mail using Webmail?
If so, you should be able to reset your email client password for Outlook. It would also be prudent to remove your existing account from Outlook and set it up again.
To create one or update an existing one you need to follow these steps:
Sign into the My Virgin media account for the email concerned with your VMO2ID
Select Account Settings
Select Identity & Security Settings
Select Manage your products
Select Manage email app password
Click on the blue button 'Get New Password'
Make a note of the generated password. This is what you use in the mail apps along with the ntlworld email address as the username.