Welcome to the Community, I'm sorry to learn about the problems you're experiencing with Netflix on your TiVo box at the moment.
I've been able to locate your account and take a closer look at this from our end, we're not detecting any issues with the box right away. If you're able to reboot the box after reading this message, so I can run a few more checks, that would be great.
Before doing that, can you go throuh the following:
Press Home on your TiVo remote
Select Help & Settings.
Select Connect to the Virgin Media Service now
After doing that and rebooting the box, give Netflix another go and let me know how it goes