The following may just work..
Turn off the V6 at switch; then on the V6 box hold down both the power button and the +button at the same time. Then turn on the V6 again whilst keeping hold of those buttons for a further 30 seconds. The box should reboot, the power button will turn blue, and it should reset and boot up normally.
If this fails, then as above - a TV box that won't bootup has a fault, so you'll need to report that fault. Either call in for an immediate response, or wait here for VM staff to respond, if you don't mind waiting a couple of days. The lead-time for a tech attendance is likely to be ~3 days from whenever it's booked.
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