if you're asking about an internet-connected TV rather than a Virgin TV box, then check that both pieces of kit are connecting to the same WiFi network - by default, a VM hub broadcasts 2.4Ghz & 5Ghz bands on the same SSID and I believe the Hub admin is the only way to be sure, without splitting the bands out.
If both your TV and phone are connecting to the same band, then it sounds like there may be a fault with the TV.
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