When you say "computer is working", is that connected to the Hub by ethernet cable and it is just wifi that is down? Unlikely to be related to the O2 issue.
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Services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired 2 WiFi,) SH2 in modem mode with Airport Extreme Router. On VIVID200, Talk Anytime Phone, x2 Mobile SIM only iPhones.