You have to set up the remote to control the TV. It's under Settings->Remotes & devices->Remotes->"Voice remote"->Set up remote for TV control. The next problem you may run into is that when you enter your TV's brand (or any brand) no results are shown.
Once you do get it set up to control the TV, pressing any of the TV control buttons will not be acknowledged by the stick. They only control the TV and have no effect on the stick.
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