I'm sorry to hear that your TV box isn't turning on. Provided all the power cables are secure in the back of the box, we will need to replace the box.
I've arranged an engineer visit for you so the box can be replaced if needed. To view your appointment time slot, please head over to your my Virgin Media account and go to 'my appointments and orders'.
Let us know how the visit goes and give us a shout if you need anything else.