I have a TCL Roku TV model 49S405 with OS version 9.2.0 build 4502-30. My existing Google Assistant routine stopped working, and I've isolated it to one command. This command had not changed, and was working on prior OS builds.
"Change to channel 4.1 on Roku TV" reports that something went wrong. Removing the ".1" portion still works, but now Google Assistant can't select antenna subchannels.