Try hiding the Streaming Channels under Settings/TV Inputs/Manage Channels/Hide Streaming Channels.
Then do a reboot of the RokuTV from Settings/System/Power/System Restart.
After the RokuTV reboots, select/launch the Antenna TV icon from the Home Screen. (Do not use the LiveTV from the left side Menu.)
After AntennaTV launches, use the left arrow button on remote to bring up Guide. (Otherwise just use up and down arrows to channel up or down).
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See if the above helps your issue and post back what you are seeing if still having issues.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102