I had the same problem, symptom was the smart remote power button worked, but nothing else. Also, my smartphone TV remote app didn't work either, so I suspected the TV. First I did a hard reset on the remote (remove batteries, press any button for 20-30 seconds) and replaced the batteries, that didn't help. Unplugged the TV, waited a minute, pressed and held the power button for 30 seconds. Plugged it back in and everything is working now.