Some smart TVs update when you turn them off. So I'm unsure what you are telling the forum here. Other than it runs for 5 minutes after your turn it off, it works fine? If so, call Samsung and ask them to explain. In the USA it's 1800SAMSUNG and for other countries look at samsung.com
Tv runs on by itself approx 4-5 minutes after being turned off. Any ideas what the problem could be?