@Bavnah-
Roku devices and Roku TVs use different sets of infrared control codes. A Roku Express infrared remote (formerly called the "simple" remote, now called the "players" remote) will not work with a Roku TV.
Any of the Roku Voice Remote models can be used with a Roku TV. They connect via WiFi direct and must be paired with the Roku it is to be used with.
You also can find a direct replacement remote specifically for Roku TVs (either generic or for specific TV brands, all are interchangeable) at many retailers, on Amazon, and directly from Roku.
Also many inexpensive universal infrared remote controls contain codes for Roku TVs, just be sure it says it will control "Roku TV" not just a "Roku".
Roku Community Streaming Expert
I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well.
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