If I'm following you, you have a Roku TV with a Roku Ultra connected to it, right? The banner is coming from the TV, not the Ultra (you probably already know that). Was the TV set up for "store mode"? You might want to factory reset the TV (not the Ultra) and start over. If you don't plan on using the the TV's Roku features just don't link it to your Roku account (or connect it to your network for that matter). It will have a bare minimum Home Screen with the TV's inputs and live OTA (antenna) as tiles. I have a TCL Roku TV set up like this. My Roku stick will make the TV switch to the stick's HDMI input when I press Home on its remote and the remote can be configured to control the power and volume of the TV. I only need the TV's remote to access things like picture settings and to change to a different HDMI input. I rarely watch OTA channels on this particular TV, but that would require the TV's remote as well.
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