Router wont allow new wired devices to join network, its a BT Home Hub 5A running OpenWrt 19.07.2 r10947-65030d81f3 / LuCI openwrt-19.07 branch git-20.057.55219-13dd17f. Plusnet fibre.
I had a power cut in September and my tv box stopped connecting it was old so wasn't bothered about it, went I tried to switch on heating found out the Hive hub wasn't connected to the network. Been sent a new hIve hub and it wont connect either. Wireless connections are ok, the problem is with the wired connections - DHCP requests being made but not being assigned IP. I am very new to OpenWrt, so I am thinking that sw on router has corrupted?
You can always try to flash 19.07.4 (you should, anyway), without saving configuration and see if this will solve the solution.
To rule out any issue with DHCP (not that I expect that), you could set a static IP on a computer, connect it to the router and see if you can access it.
Edit: keep the settings, because otherwise you would be locked out of wifi is off and the switch is actually damaged.
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