I am having the same problem. If the router is restarted (power failure etc) then the 2.4Ghz channel does not restart. I work-a-round by logging into the VirginMedia router: Advanced Settings > Wireless Signal Disabled Wireless frequency 2.4 GHz disable then save then enable and save.
The problem with this is that if I'm away my security cameras (Ring) and central heating (Nest) loose connection.
I would imagine that this is a software problem. Is there a fix?
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