I somehow lost the settings option in the navigation menu. It only shows About. On the DVR Web UI settings I have turned off Kisok mode for both the AppleTV client and the Server side settings. I used to have settings on the AppleTV client but no more.
AppleTV version 4.5.9
DVR version 2021.08.12.0054
Maybe force quit and restart the app? Click TV/Home on the Siri remote twice and then swipe up on the Channels app
I've done that many times. No go. 
You wouldn't happen to have the beta version installed, too? Both the regular and beta version share settings; as long as at least some version of Channels is installed, the settings will persist.
For AppleTV I've only installed the App Store version and have not use beta (testflight) versions.
We it's working now and I'm not sure exactly why. I upgraded DVR to pre-release 2021.09.18.2207. Then I set the AppleTV client to override kisok mode, and set it to turn off kisok mode. The global client setting override was not set to override kisok mode before I changed anything on the AppleTV client. I'm happy it's back. Thanks for the suggestions.
You had it forced to on so it stayed on. You needed to force it to off at which point it returned.