A few possibilities here.
1: The V6 needs 2 connections - coax for the live TV channels, wired/wireless to your homehub for the internet. Are both present?
2: All TiVo/V6 that aren't connected to VM's network for a certain amount of time are liable to be deactivated, and 4months is plenty long enough for this to have happened. You'll need to call 0800 9539500 with the box details to hand, to reactivate it.
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