I'm very sorry to hear that has happened. In order for me to help you most accurately, please provide the complete model code for this device.
I connected HBOGO thru an ipad to the Samsung tv. We watched a movie, and when it was done, I had this problem. My tv is playing Turner Classic Movies thru the Smart Hub and it will not stop. I cannot find a way to exit Smart Hub. I unplugged the tv, I cut power to all tv connected devices, I cut power to my wireless router. This is a 2012 tv. I tried reconnecting the network. Help.