I assume you mean you have a V6 connected to your Hub by ethernet cable. If so switch them both off and unplug from the mains for 5 minutes. Pull ethernet cable out from the V6. Then start up the Hub and check that it has connected fine to the network and another device has an internet connection. Then put the ethernet cable back into the V6 and start it up. It should remake the connection ok. If it doesnt - repeat the process with a new Cat5e/6a ethernet cable - in case it has gone faulty.
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