I agree with cazuela, you've got a demo mode setup on your tv. I had that problem when they came to change a hdmi port on my tv and the automatic seeing for the tv was demo mode and it kept on coming with the 4k demo that was built in.
Doesn't even need to be connected to the Internet for the demo mode to come on, it's set to come on after a certain period of time.
Deffinately what's causing the problem here
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