I am trying to switch the account my hub is registered to. I removed the hub device from the old account, but when I open the device it still shows it is registered to that account. When I go to my.hubitat.com/hubs and am logged in with the old account it shows "There are no hubs associated with email ****."
Have you tried rebooting the hub? If you de-registered the hub while logged into the old account, then log out of my.hubitat.com and log in with your new account. Then connect to your hub and go to Settings then Hub Details. Scroll down on the page and you should see a notification to "Register your hub". If that doesn't work, please send me a private message and we will further assist you.