Hi there @Atrew
Thanks for popping back. I have checked the IT ticket that was raised (P010135893) and this is showing as fixed as of this morning. They have advised that they have reset the details and ensured everything is now ready to use on the App as well as your online account.
In order to sync them your end, please log into your MyVirginMedia account and reset your password. Then please remove and delete the app from the device - reinstall and try logging in with your new password
Let me know how you get on.
Cheers