Are you still having this issue? If so, could you send us the full model code and software version of your TV? Go to Home > Settings > Support > About This TV.
Unplug from the wall and leave it unplugged for a while. If possible, unplug it and just go out to work or whatever and plug it back in hours later. I am assuming pressing the menu button doesnt allow you into the TV menu to do a reset of the smart hub?
If it is still in the same state I have seen this advice before to force a factory reset (but it might be old advice):
Make sure that your TV is OFF.
Simultaneously press Info + Menu + Mute + Power on your remote
Next, enter the following sequence into your remote: Mute > 1 > 8 > 2 > Power.
Your television will boot up in service mode. Using your remote, go to Options > Factory Reset.