Unreliable service

Hi,

Since having fibre installed in January this year I am constantly having disconnection issues, drops offline and I get the slow white flashing light, usually it comes back on if I power it down and back on and lasts a couple weeks max, now it's started being a daily thing but today it's gone off and will not come back on, Virgin cannot fix so what can I do because it's completely unreliable and I need the internet for medical equipment, I have a hub 5x and it's full fibre on 250mb contract, anyone advise, thanks