I'm gonna guess that you don't have a TiVo but actually a V6 (check here if you're not sure). The V6 gets its internet connection from your homehub, and by changing that it's not had a 'net connection. That will have broken OnDemand, and the box's ability to update the TV guide. Resulting in no EPG info.
Home > Help & Settings > Settings > Network, follow the prompts.
I'm a Very Insightful Person, I'm here to share knowledge, I don't work for Virgin Media. Learn more
Have I helped? Click Mark as Helpful Answer or use Kudos to say thanks