A CS agent offering to monitor your box is, IMO, an excuse to get you off the phone without actually resolving what is clearly a fault. It shouldn't happen, but unfortunately does.
I would agree you need a tech visit which may well result in your V6 being replaced. From here, you have 2 options..
1: Call back, get a different agent and hopefully the correct outcome
2: Wait here, and in a couple of days, VM staff should respond and do the honours instead.
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