@AB2 Apple, bless their little cotton socks, do love giving security warnings. What your phone is telling you is that the Sky hub is not running a new security standard called WPA3 which the latest routers run. Instead the Sky black hubs, like almost every other router that wasn't designed in the last 2 years, defaults to an older standard WPA2-PSK which most of the industry accepts is secure.so unless you have changed your hub's security settings your Wifi network is secure.
Sky do have a new white hub that does support WPA3 which comes as part of the Wifi Max package but dont upgrade to shut your phone up as its pointless as the threat of wifi hacking is incredibly remote.
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65inch Sky Glass, 3 Sky Streaming Pucks, Sky Ultrafast + and Sky SR213(white Wifi Max hub) main Wifi from 3 TP-Link Deco M4 units in access point mode
