@heyday I don’t know where you get this plug and unplug method for reseting a v2 Hub, that is for the v3 Hubs.
SmartThings Hub v2
Press and hold the red recessed button the back of the Hub for 30 seconds. When the LED on the front switches from flashing yellow to solid yellow, release the button.
Note: make sure the Hub is plugged in with the included power and Ethernet cables. Do not disconnect the cables.
Odd enough someone posted a similar issue just a day ago…