Hi, @funsuk61
Warm greetings here in the Roku community.
We acknowledge that you are inquiring about using the remote on a specific Roku device, and we're here to assist.
On one of your Roku devices, you can choose one to be navigated by only one remote, and here's how.
1. Navigate to Settings > Remotes & Devices > Remotes.
2. Select the remote that controls your device.
3. Remove the remote that you no longer want to be connected to your Roku device, and follow the on-screen instructions.
Hope this works.
All the best,
Kash
Takashi O.
Roku Community Moderator