Have you tried a factory reset? Hold in the pinhole at the rear of the router for at least 50 seconds and then release (the lights will flash while holding in the pinhole reset button after about 10-15 seconds) then allow 5 minutes for the router to reboot and re-sync the connection.
If this doesn't cure the problem you would probably be better of investing in a decent third party router, that way you can put the Virgin Hub into modem mode and let the router deal with all the traffic. This would give you better wi-fi coverage and if you go for the likes of a wi-fi 6 capable router you would get better speeds. There are loads of options from Asus, TP Link etc and seeing as the VM Hubs are well known for their lack of wi-fi capabilities you would be better of using your own equipment, especially if you are suffering from poor wi-fi coverage and speed. I know it's a case of having to spend money that you shouldn't have to, but it really is worth it and gives you a better all round internet experience
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Super Hub 4.0 (modem mode) - Gig1 Fibre FTTP - Asus RT-AX82U & Asus RT-AX56U with AiMesh setup
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