@vaxxee
Refer to this thread and make sure you are selecting the LiveTV "Input" from the Home Screen (do not use the LiveTV from the left side menu). Further suggest you Rename this Input from LiveTV to Antenna TV from within Settings/TV Inputs/rename.
https://community.roku.com/t5/Solving-playback-issues/Antenna-Channels-disappears-every-time-I-turn-...
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