First of all I would recommend that you check the 'Service Status' link after logging into your Virgin Media online account. This will show if there are any known issues in your area which are likely to be causing this fault.
Also do you have another phone you are able to try in case the phone has developed a fault ?
There are staff members that respond to posts on this public forum but it seems to take them around a week to reply, so relying on that wouldn't be the fastest option for you. You could give them a call or contact them via Live Chat
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