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Had a similar problem just now at 0916.
The wifi light on my laptop went out.
Network diagnostics suggested "Verify Network Security key" Verified it.
Then diagnostics found "A Network cable is not plugged in or is broken" Not so cable is fine.
At 0920 the connection was Re-established, wfi light on laptop illuminated again.
No idea what caused it.
did you try resetting the hub using recessed button on back