Tried turning the power off for a couple of minutes then reconnecting it? Maybe do that a few times?
If that doesn't get you anywhere it may be a hardware problem. Call 150 for free from a Virgin phone or 0345 454 1111 (paid) from any other phone, or wait for a few days for admins to see and reply to your post here.
If the only 'fix' is a replacement TiVo box or reset you will lose your recordings though.